you do not want to know, esp. because the information is embarrassing or upsetting The movie has lots of scary parts, and a particularly nasty suicide - don't ask.
Usage notes: used to say that you do not want to give any more information about a subject
A phrase used to fend off questions about a situation one finds awkward, unpleasant, or unsatisfactory. For example, How did we do in the bridge tournament? Don't ask! [Colloquial; 1960s] For a similar phrase, see forget it.