disinterested vs. uninterested

In modern English, disinterested primarily means “impartial or free from bias,” while uninterested simply means “not interested or caring; indifferent.” For example:

These two terms are often used interchangeably (with disinterested being more common) because of the similarity in meaning between the prefixes “dis-” and “un-”, and because the specific usage of interested (“partial or biased”) is less common than the more general meaning of “caring or having an interest.”

Stricter grammarians decry using the two terms interchangeably, maintaining that they should only be used to express the separate meanings above (it is especially frowned upon to use uninterested to mean “impartial or unbiased”). In reality, the distinction has been eroded in recent years, and disinterested is very commonly used instead of uninterested. It’s also worth mentioning that the original meanings of these words were actually the opposite until the 1700s, so there is historical precedence in using the two words in both ways.

However, especially in more formal writing, it is best to maintain the modern distinction in meaning between the two different terms, because it is always correct to do so.