Wordwatch Towers

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Underestimate or overestimate?

with 9 comments


You may need tea or something stronger for this.

Heard on BBC Radio 4 during a conversation about a doctor wrongly accused of misconduct:

You cannot underestimate the effects of a case like this on an individual.

Underestimate? Is that right? Shouldn’t the speaker have said ‘overestimate’?

Overestimate means ‘to form too high an estimate of’ (see Oxford Dictionaries).

Underestimate means to estimate that something is smaller or less important than it actually is (see Oxford Dictionaries).

So what did the speaker on Radio 4 mean to say?

Here’s how I see it:

If I cannot underestimate the effect on the doctor, then I could say that the effect was minuscule — but it could be even smaller than that.

If I cannot overestimate the effect, then however great I estimate the effect to be, it could be even greater.

So, the Radio 4 speaker should have said:

You cannot overestimate the effects of a case like this on an individual.

See an excellent discussion about this in theGuardian newspaper.

More commonly confused words


9 Responses

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  1. Ha! Good point. Most of us would read right by the error and get the intent. I shall be extra vigilant hereinafter.

    (By the by, just ’cause y’all invented the language doesn’t mean you get to nitpick over “cannot” and “ought not.” That is pure pedantry.)

    Michael Farrell

    28/02/2010 at 4:44 pm

  2. You’re right – in most cases people automatically understand what is meant. For some reason, I always notice when either of these two words is used wrongly — especially when a serious point is being made.

    I’d just like to leave this hanging in the air:

    In my introduction to The King’s English by Fowler and Fowler, Matthew Parris (UK newspaper columnist) posed this question:

    “Is ‘to nitpick’ a split infinitive?”


    28/02/2010 at 5:14 pm

    • No. “Nitpick” is a valid verb — I said so — and, in any event, the infinitive is “nitpick,” not “to nitpick.” I cannot underestimate how much I could care less.

      Michael Farrell

      28/02/2010 at 5:25 pm

  3. Guy Keleny in The Independent‘s Errors & Omissions column:

    Good estimate: Last week I wondered why writers so often use “underestimate” when they mean “overestimate”, as in “The wickedness of the Government cannot be underestimated.”

    Mark Miller writes from Dalton-in-Furness, Cumbria, to suggest that “should not be underestimated” has shifted to “cannot be underestimated”. He points to the way we often use “cannot” to mean “should not”, as in “You can’t go out like that” or “You can’t ignore this book”. But when “should not be underestimated” becomes “cannot be underestimated”, we have sleepwalked into saying the opposite of what we mean. It sounds plausible.


    05/01/2011 at 6:15 pm

  4. From a hospital information leaflet:

    The therapeutic role of food within the healing process cannot be underestimated.


    13/01/2011 at 1:46 pm

    • Yet most hospitals continually underestimate its role. Do you have Jello over there?

      Michael Farrell

      21/01/2011 at 6:11 am

      • …and some hospital chefs overestimate their ability to create anything even vaguely therapeutic on the food front. I’m not familiar with Jello; it sounds very American.


        21/01/2011 at 9:39 pm

  5. The latest from Guy Keleny (The Independent) on this:

    More is less: Hamish McRae wrote in his Wednesday column: “It is hard to underestimate the significance of what is happening in Germany over nuclear power.” He meant to say that the significance is very big. People of a pedantic turn would say he should have written that it is hard to overestimate. I would take that view, but the “underestimate” usage is very common. What is the thought process?

    Those of us who think a big thing is hard to overestimate are, I think, picturing something like a scale of 1 to 10. It is marked with a bar near the top, at 9 or 9.5. That is the size of the big thing. Obviously, there is less space above the bar than below, so there is less scope to overestimate the quantity than to underestimate it. Ergo, it is hard to overestimate.

    Those who think the big thing is hard to underestimate are, I think, taking the word “underestimate” to mean “make light of”. So huge is the hugeness of the big thing that the mind cannot possibly make the mistake of thinking it small – that is their thinking.

    Perhaps we should just drop this “hard to overestimate/underestimate” thing, since it is so easy to take it either way.

    Variation on a theme: understate/overstate

    From the New York Times’ After Deadline column:

    Tim Thomas’s importance to the Boston Bruins cannot be understated.

    We meant “cannot be OVERstated” — that is, his importance is so great that exaggerating it would be impossible. Writers frequently get this wrong, perhaps confusing it with a related idea like “SHOULD not be understated.”


    04/04/2011 at 9:34 am

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