Primary Meanings of weed

any plant that crowds out cultivated plants
clear of weeds
a black band worn by a man (on the arm or hat) as a sign of mourning
Full Definitions of weed

n any plant that crowds out cultivated plants

cultivated plant
plants that are grown for their produce
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Agrostemma githago, corn campion, corn cockle, crown-of-the-field
European annual having large trumpet-shaped reddish-purple flowers and poisonous seed; a common weed in grainfields and beside roadways; naturalized in America
Scleranthus annuus, knawe, knawel
widely distributed low-growing Eurasian herb having narrow leaves and inconspicuous green flowers
Spergula arvensis, corn spurrey, corn spurry
small European weed with whorled leaves and white flowers
Spergularia rubra, sand spurry, sea spurry
prostrate weedy herb with tiny pink flowers; widespread throughout Europe and Asia on sand dunes and heath and coastal cliffs; naturalized in eastern North America
Indian chickweed, Molluga verticillata, carpetweed
annual prostrate mat-forming weed having whorled leaves and small greenish-white flowers; widespread throughout North America
Alternanthera philoxeroides, alligator grass, alligator weed
prolific South American aquatic weed having grasslike leaves and short spikes of white flowers; clogs waterways with dense floating masses
Barbarea vulgaris, Sisymbrium barbarea, rockcress, rocket cress, yellow rocket
noxious cress with yellow flowers; sometimes placed in genus Sisymbrium
Erysimum cheiranthoides, wormseed mustard
slender yellow-flowered European mustard often troublesome as a weed; formerly used as an anthelmintic
Raphanus raphanistrum, jointed charlock, runch, wild radish, wild rape
Eurasian weed having yellow or mauve or white flowers and podlike fruits
any of several plants of the genus Thlaspi
ambrosia, bitterweed, ragweed
any of numerous chiefly North American weedy plants constituting the genus Ambrosia that produce highly allergenic pollen responsible for much hay fever and asthma
any of numerous plants of the family Compositae and especially of the genera Carduus and Cirsium and Onopordum having prickly-edged leaves
Barnaby's thistle, Centaurea solstitialis, yellow star-thistle
European weed having a winged stem and hairy leaves; adventive in the eastern United States
Canadian fleabane, Conyza canadensis, Erigeron canadensis, fleabane, horseweed
common North American weed with linear leaves and small discoid heads of yellowish flowers; widely naturalized throughout temperate regions; sometimes placed in genus Erigeron
Erechtites hieracifolia, fireweed
an American weedy plant with small white or greenish flowers
Hieracium praealtum, king devil, yellow hawkweed
European hawkweed introduced into northeastern United States; locally troublesome weeds
California dandelion, Hypochaeris radicata, capeweed, cat's-ear, gosmore
European weed widely naturalized in North America having yellow flower heads and leaves resembling a cat's ears
Parthenium hysterophorus, bastard feverfew
tropical American annual weed with small radiate heads of white flowers; adventive in southern United States
Picris echioides, bitterweed, bristly oxtongue, bugloss, oxtongue
widespread European weed with spiny tongue-shaped leaves and yellow flowers; naturalized in United States
Hieracium aurantiacum, Pilosella aurantiaca, orange hawkweed
European hawkweed having flower heads with bright orange-red rays; a troublesome weed especially as naturalized in northeastern North America; sometimes placed in genus Hieracium
Senecio doublasii, threadleaf groundsel
bluish-green bushy leafy plant covered with close white wool and bearing branched clusters of yellow flower heads; southwestern United States; toxic to range livestock
Senecio jacobaea, benweed, ragweed, ragwort, tansy ragwort
widespread European weed having yellow daisylike flowers; sometimes an obnoxious weed and toxic to cattle if consumed in quantity
Senecio vulgaris, groundsel
Eurasian weed with heads of small yellow flowers
cockle-bur, cockle-burr, cocklebur, cockleburr
any coarse weed of the genus Xanthium having spiny burrs
any of numerous plants having stinging hairs that cause skin irritation on contact (especially of the genus Urtica or family Urticaceae)
any plant that breaks away from its roots in autumn and is driven by the wind as a light rolling mass
madnep, wild parsnip
biennial weed in Europe and America having large pinnate leaves and yellow flowers and a bitter and somewhat poisonous root; the ancestor of cultivated parsnip
French weed, Thlaspi arvense, fanweed, field pennycress, mithridate mustard, penny grass, stinkweed
foetid Eurasian weed having round flat pods; naturalized throughout North America
Ambrosia artemisiifolia, common ragweed
annual weed with finely divided foliage and spikes of green flowers; common in North America; introduced elsewhere accidentally
Ambrosia trifida, great ragweed
a coarse annual with some leaves deeply and palmately three-cleft or five-cleft
Ambrosia psilostachya, perennial ragweed, western ragweed
coarse perennial ragweed with creeping roots of dry barren lands of southwestern United States and Mexico
Carduus crispus, welted thistle
European biennial introduced in North America having flower heads in crowded clusters at ends of branches
Carduus nutans, musk thistle, nodding thistle
Eurasian perennial naturalized in eastern North America having very spiny white cottony foliage and nodding musky crimson flower heads; valuable source of nectar
carline thistle
a thistle of the genus Carlina
plume thistle, plumed thistle
any of numerous biennial to perennial herbs with handsome purple or yellow or occasionally white flower heads
Cirsium discolor, field thistle
stout North American thistle with purplish-pink flower heads
Cirsium helenioides, Cirsium heterophylum, melancholy thistle
perennial stoloniferous thistle of northern Europe with lanceolate basal leaves and usually solitary heads of reddish-purple flowers
Cnicus benedictus, blessed thistle, sweet sultan
annual of Mediterranean to Portugal having hairy stems and minutely spiny-toothed leaves and large heads of yellow flowers
Onopordon acanthium, Onopordum acanthium, Scotch thistle, cotton thistle, woolly thistle
biennial Eurasian white hairy thistle having pale purple flowers; naturalized in North America
golden thistle
any of several spiny Mediterranean herbs of the genus Scolymus having yellow flower heads
Urtica dioica, stinging nettle
perennial Eurasian nettle established in North America having broad coarsely toothed leaves with copious stinging hairs
Roman nettle, Urtica pipulifera
annual European nettle with stinging foliage and small clusters of green flowers
Laportea canadensis, wood nettle
American perennial herb found in rich woods and provided with stinging hairs; provides fibers used for textiles
Pilea pumilla, clearweed, dead nettle, richweed
a plants of the genus Pilea having drooping green flower clusters and smooth translucent stems and leaves
Pilea microphylla, artillery plant
tropical American stingless nettle that discharges its pollen explosively
Pilea involucrata, friendship plant, panamica, panamiga
low stingless nettle of Central and South America having velvety brownish-green toothed leaves and clusters of small green flowers
Type of:
tracheophyte, vascular plant
green plant having a vascular system: ferns, gymnosperms, angiosperms

n street names for marijuana

Type of:
cannabis, ganja, marihuana, marijuana
the most commonly used illicit drug; considered a soft drug, it consists of the dried leaves of the hemp plant; smoked or chewed for euphoric effect

v clear of weeds

weed the garden”
clear of weeds by uprooting them
Type of:
remove, take, take away, withdraw
remove something concrete, as by lifting, pushing, or taking off, or remove something abstract

n a black band worn by a man (on the arm or hat) as a sign of mourning

mourning band
Type of:
a thin flat strip of flexible material that is worn around the body or one of the limbs (especially to decorate the body)

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