Verb
stick out like a sore thumb (third-person singular simple present sticks out like a sore thumb, present participle sticking out like a sore thumb, simple past and past participle stuck out like a sore thumb)
(simile) Be very noticeably different, especially in a negative way; to be particularly obtrusive, conspicuous, blatant, or prominent; to attract undue attention or notice.
Synonym: stick out a mile