To underestimate is to guess that something is worth less or is smaller than it really is. You might underestimate the size of a one-pound hamburger until you realize it's too big to fit in your stomach.

When you "estimate" you take a guess at something, and when you underestimate, your guess falls short or below. If you underestimate how much something costs, you might show up at a store without enough money, and if you underestimate the strength of an opponent who is small, you might find yourself on the ground wondering what hit you. Often when we "assume" something, we make a guess based on how things appear — that's one way to underestimate.

Definitions of underestimate
  1. verb
    make too low an estimate of
    “he underestimated the work that went into the renovation”
    “Don't underestimate the danger of such a raft trip on this river”
    synonyms: underrate
    see moresee less
    overestimate, overrate
    make too high an estimate of
    sell short
    underestimate the real value or ability of
    type of:
    judge incorrectly
  2. verb
    assign too low a value to
    “Don't underestimate the value of this heirloom-you may sell it at a good price”
    synonyms: undervalue
    see moresee less
    overestimate, overvalue
    assign too high a value to
    type of:
    fix or determine the value of; assign a value to
  3. verb
    make a deliberately low estimate
    synonyms: lowball
    see moresee less
    type of:
    approximate, estimate, gauge, guess, judge
    judge tentatively or form an estimate of (quantities or time)
  4. noun
    an estimation that is too low; an estimate that is less than the true or actual value
    synonyms: underestimation, underrating, underreckoning
    see moresee less
    type of:
    approximation, estimate, estimation, idea
    an approximate calculation of quantity or degree or worth
Word Family

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