Definitions of os
  1. noun
    a mouth or mouthlike opening
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    type of:
    opening, orifice, porta
    an aperture or hole that opens into a bodily cavity
  2. noun
    rigid connective tissue that makes up the skeleton of vertebrates
    synonyms: bone
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    a forked bone formed by the fusion of the clavicles of most birds
    splint bone
    a rudimentary metacarpal or metatarsal bone on either side of the cannon bone in the leg of a horse or related animal
    fetter bone, pastern
    the part between the fetlock and the hoof
    cannon bone
    greatly developed metatarsal or metacarpal bone in the shank or cannon part of the leg in hoofed mammals
    a bone of a fish
    anklebone, astragal, astragalus, talus
    the bone in the ankle that articulates with the leg bones to form the ankle joint
    bare bone
    bone stripped of flesh
    cuboid bone
    the cube shaped bone on the outer side of the tarsus
    carpal, carpal bone, wrist bone
    any of the eight small bones of the wrist of primates
    cartilage bone
    any bone that develops within cartilage rather than a fibrous tissue
    the main body of a vertebra
    cheekbone, jugal bone, malar, malar bone, os zygomaticum, zygomatic, zygomatic bone
    the arch of bone beneath the eye that forms the prominence of the cheek
    clavicle, collarbone
    bone linking the scapula and sternum
    coccyx, tail bone
    the end of the vertebral column in humans and tailless apes
    dentin, dentine
    bone (calcified tissue) surrounding the pulp cavity of a tooth
    ethmoid, ethmoid bone
    one of the eight bones of the cranium; a small bone filled with air spaces that forms part of the eye sockets and the nasal cavity
    calcaneus, heelbone, os tarsi fibulare
    the largest tarsal bone; forms the human heel
    hipbone, innominate bone
    large flaring bone forming one half of the pelvis; made up of the ilium and ischium and pubis
    hyoid, hyoid bone, os hyoideum
    a U-shaped bone at the base of the tongue that supports the tongue muscles
    the upper and widest of the three bones making up the hipbone
    ischial bone, ischium, os ischii
    one of the three sections of the hipbone; situated below the ilium
    long bone, os longum
    in limbs of vertebrate animals: a long cylindrical bone that contains marrow
    the posterior part of the mandible that is more or less vertical
    membrane bone
    any bone that develops within membranous tissue without previous cartilage formation; e.g. the clavicle and bones of the skull
    metacarpal, metacarpal bone
    any bone of the hand between the wrist and fingers
    any bone of the foot between the ankle and the toes
    nasal, nasal bone, os nasale
    an elongated rectangular bone that forms the bridge of the nose
    bonelet, ossicle, ossiculum
    a small bone; especially one in the middle ear
    os palatinum, palatine, palatine bone
    either of two irregularly shaped bones that form the back of the hard palate and helps to form the nasal cavity and the floor of the orbits
    any of the bones of the fingers or toes
    os pubis, pubic bone, pubis
    one of the three sections of the hipbone; together these two bones form the front of the pelvis
    costa, rib
    any of the 12 pairs of curved arches of bone extending from the spine to or toward the sternum in humans (and similar bones in most vertebrates)
    round bone
    bones that are round in shape
    wedge-shaped bone consisting of five fused vertebrae forming the posterior part of the pelvis; its base connects with the lowest lumbar vertebra and its tip with the coccyx
    scapula, shoulder blade, shoulder bone
    either of two flat triangular bones one on each side of the shoulder in human beings
    os sesamoideum, sesamoid, sesamoid bone
    any of several small round bones formed in a tendon where it passes over a joint
    os breve, short bone
    a bone that is of approximately equal dimension in all directions
    os sphenoidale, sphenoid, sphenoid bone
    butterfly-shaped bone at the base of the skull
    breastbone, sternum
    the flat bone that articulates with the clavicles and the first seven pairs of ribs
    corpus sternum, gladiolus
    the large central part of the breastbone
    the upper part of the breastbone
    xiphoid process
    smallest of the three parts of the breastbone; articulates with the corpus sternum and the seventh rib
    tarsal, tarsal bone
    any bone of the tarsus
    os temporale, temporal bone
    a thick bone forming the side of the human cranium and encasing the inner ear
    hard bonelike structures in the jaws of vertebrates; used for biting and chewing or for attack and defense
    turbinal, turbinate, turbinate bone
    any of the scrolled spongy bones of the nasal passages in man and other vertebrates
    tympanic bone
    the bone enclosing the middle ear
    one of the bony segments of the spinal column
    arcus zygomaticus, zygoma, zygomatic arch
    the slender arch formed by the temporal process of the cheekbone that bridges to the zygomatic process of the temporal bone
    the central conical bony pillar of the cochlea
    lacrimal bone
    small fragile bone making up part of the front inner walls of each eye socket and providing room for the passage of the lacrimal ducts
    the bony skeleton of the head of vertebrates
    calvaria, skullcap
    the dome of the skull
    braincase, brainpan, cranium
    the part of the skull that encloses the brain
    back part of the head or skull
    the front part of the head or skull (including the forehead)
    the part of the skull of a vertebrate that frames the mouth and holds the teeth
    thin trapezoidal bone of the skull forming the posterior and inferior parts of the nasal septum
    Wormian bone, sutural bone
    any of the tiny soft bones found in the sutures between cranial bones
    a bone containing edible marrow; used especially in flavoring soup
    hollow or grooved tooth of a venomous snake; used to inject its poison
    a long pointed tooth specialized for fighting or digging; especially in an elephant or walrus or hog
    the tiny fossil cone-shaped tooth of a primitive vertebrate of order Conodonta
    wishbone, wishing bone
    the furcula of a domestic fowl
    nasal concha
    one of several turbinate bones in the nasal cavity
    navicular, os scaphoideum, scaphoid bone
    the largest wrist bone on the thumb side
    lunate bone, os lunatum, semilunar bone
    one of the eight small wrist bones
    cuneiform bone, os triquetrum, pyramidal bone, triquetral, triquetral bone
    a wrist bone that articulates with the pisiform and hamate and lunate bones
    os pisiforme, pisiform, pisiform bone
    a small wrist bone that articulates only with the triquetral
    os trapezium, trapezium, trapezium bone
    the wrist bone on the thumb side of the hand that articulates with the 1st and 2nd metacarpals
    os trapezoideum, trapezoid, trapezoid bone
    the wrist bone between the trapezium and the capitate bones
    capitate, capitate bone, os capitatum
    the wrist bone with a rounded head shape that articulates with the 3rd metacarpus
    hamate, hamate bone, os hamatum, unciform bone
    the wrist bone in line with the 4th and 5th fingers
    jawbone, jowl, lower jaw, lower jawbone, mandible, mandibula, mandibular bone, submaxilla
    the jaw in vertebrates that is hinged to open the mouth
    auditory ossicle
    ossicles of the middle ear that transmit acoustic vibrations from the eardrum to the inner ear
    kneecap, kneepan, patella
    a small flat triangular bone in front of the knee that protects the knee joint
    chopper, pearly
    informal terms for a human `tooth'
    carnassial tooth
    the last upper premolar and first lower molar teeth of a carnivore; having sharp edges for cutting flesh
    maxilla, maxillary, upper jaw, upper jawbone
    the jaw in vertebrates that is fused to the cranium
    anterior, front tooth
    a tooth situated at the front of the mouth
    back tooth, posterior
    a tooth situated at the back of the mouth
    malposed tooth
    a tooth that has grown in a faulty position
    adult tooth, permanent tooth
    any of the 32 teeth that replace the deciduous teeth of early childhood and (with luck) can last until old age
    baby tooth, deciduous tooth, milk tooth, primary tooth
    one of the first temporary teeth of a young mammal (one of 20 in children)
    canine, canine tooth, cuspid, dogtooth, eye tooth, eyetooth
    one of the four pointed conical teeth (two in each jaw) located between the incisors and the premolars
    bicuspid, premolar
    a tooth having two cusps or points; located between the incisors and the molars
    a tooth for cutting or gnawing; located in the front of the mouth in both jaws
    grinder, molar
    grinding tooth with a broad crown; located behind the premolars
    forehead, frontal bone, os frontale
    the large cranial bone forming the front part of the cranium: includes the upper part of the orbits
    parietal bone
    either of two skull bones between the frontal and occipital bones and forming the top and sides of the cranium
    occipital bone
    a saucer-shaped membrane bone that forms the back of the skull
    a jaw
    cervical vertebra, neck bone
    one of 7 vertebrae in the human spine located in the neck region
    dorsal vertebra, thoracic vertebra
    one of 12 vertebrae in the human vertebral column; thoracic vertebrae extend from the seventh cervical vertebra down to the first lumbar vertebra
    lumbar vertebra
    one of 5 vertebrae in the human vertebral column; lumbar vertebrae extend from the twelfth thoracic vertebra down to the sacral vertebrae
    sacral vertebra
    one of 5 vertebrae in the human spine that fuse in the adult to form the sacrum
    caudal vertebra, coccygeal vertebra
    one of 4 vertebrae in the human coccyx
    true rib
    one of the first seven ribs in a human being which attach to the sternum
    the end of a long bone; initially separated from the main bone by a layer of cartilage that eventually ossifies so the parts become fused
    diaphysis, shaft
    the main (mid) section of a long bone
    arm bone
    a bone in the arm
    leg bone
    a bone of the leg
    type of:
    connective tissue
    tissue of mesodermal origin consisting of e.g. collagen fibroblasts and fatty cells; supports organs and fills spaces between them and forms tendons and ligaments
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