The English language is full of potentially confusing pairs of words that are similar but not identical and actually mean different things. Problems then arise when we’re writing too quickly, or lazily, to really think about the words we’re choosing, but in other cases we’re presented with two words that sound kind of similar and whose meanings are close enough to make them difficult to choose between

Nowhere are the battle lines more deeply drawn in usage questions than over the difference between disinterested and uninterested. According to traditional guidelines, disinterested should never be used to mean ‘not interested’ (i.e. it is not a synonym for uninterested) but only to mean ‘impartial’, as in the judgements of disinterested outsiders are likely to be more useful. Ironically, the earliest recorded sense of disinterested is for the disputed sense. Today, the ‘incorrect’ use of disinterested is widespread: around a quarter of citations in the Oxford English Corpus for disinterested are for this sense of the word

Here are a couple of examples of ‘correct’ usage of the words:

I am a disinterested observer, and thus perfectly qualified to umpire your cricket match without favouring either team unfairly

I refuse to umpire this match as I am totally uninterested in cricket because I find it tedious in the extreme

I’m disinterested in this football match as none of my favourite teams are playing

I’m uninterested in this football match because I can’t stand today’s overpaid, mollycoddled footballers

It’s possible that at your next job interview or essay marking you might be dealing with a stickler for the ‘official’ difference between these meanings. so if you choose your words appropriately you’ll have more chance of receiving a disinterested assessment of your, or your essay’s suitability than an uninterested one!