What's the antonym of recommend? For example:
I recommend that item!
I tried to use unrecommend, but the spell-checker throws an error and it sounds stupid as well!
English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. It only takes a minute to sign up.Sign up to join this community
M-W dictionary lists no antonyms.
Dictionary.com lists: disapprove, discourage, dissuade but I don't think those really fit as direct antonyms.
Usually in my experience you'd say recommend against.
---Update to add--- As FumbleFingers mentioned in a comment, advise against is an equally valid alternative (and seemingly more popular in British English, as this NGram would suggest).
Strictly speaking, discommend is the antonym, although it doesn't work in all contexts, and has become nearly obsolete.
I agree with @breen that advise against is the modern antonym phrase.
As @breen and others have said, the standard phrasing for the opposite of I recommend is probably I advise against.
But if you're not really interested in specifying who advises against something, you might consider deprecate - to express earnest disapproval of. Saying something is deprecated is standard terminology in the context of software components/methods, but there's no reason why it couldn't be used more widely.
Usage for deprecated was declining before its recent revival in computing, probably because of overlap with depreciate. But for the time being I'd stick with the past particple, and avoid, for example, "I deprecate that course of action".
Ye who arrived here as I did, hunting antonyms for this word on google, perhaps consider also:
(All definitions from Google's define command, with my italics to highlight main differences in usage, and my [comments])