From Longman Dictionary of Contemporary Englishthe last thing somebody wants/expects/needs etcthe last thing somebody wants/expects/needs etcXXsomething that someone does not want, expect etc at all The last thing I want is to upset him. The last thing I should have done was let her move into my house. → thing
Examples from the Corpus
the last thing somebody wants/expects/needs etc• I like going to bed with her when going to bed with me is the last thing she wants.• To be slipshod is to be hounded, which is the last thing he wants.• With household costs inevitably rising, the last thing he wants is a larger mortgage than he can reasonably afford. 