A protuberance is something that sticks out, like a swelling or a lump or a bunion on your foot. A protuberance doesn’t have to be hideous; it could be your nose on your face or a knot on a tree.

The late Latin word prōtūberāre meant "to swell," coming from the prefix pro, which means "forward," and the root word tūber, meaning "swelling." And "root word" is appropriate here, since a tuber is a thick, fleshy part of a root, like a potato. And that should help you remember how to spell the word protuberance. Don't you love it when a word's meaning and its spelling work together?

Definitions of protuberance
  1. noun
    something that bulges out or is protuberant or projects from its surroundings
    “the occipital protuberance was well developed”
    synonyms: bulge, bump, excrescence, extrusion, gibbosity, gibbousness, hump, jut, prominence, protrusion, swelling
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    frontal eminence
    either prominence of the frontal bone above each orbit
    occipital protuberance
    prominence on the outer surface of the occipital bone
    a part that bulges deeply
    a headlike protuberance on an organ or structure
    a bump on a ski slope
    nub, nubble
    a small lump or protuberance
    a sharp protuberance
    any small rounded protuberance (as on certain plants or animals)
    type of:
    any solid convex shape that juts out from something
  2. noun
    the condition of being protuberant; the condition of bulging out
    “the protuberance of his belly”
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    type of:
    condition, status
    a state at a particular time
Word Family

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