conspicuous by your/its absence

conspicuous by (one's)/it's absence

Especially noticeable because of being missing or absent (from something). You're the loudest one in the class, so of course you're conspicuous by your absence! The governor's economic stimulus plan was conspicuous by its absence during his speech this afternoon.
See also: absence, by, conspicuous
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

conspicuous by your/its absence

If someone or something is conspicuous by their absence, people notice that they are not there. He played no part in the game and was conspicuous by his absence at the post-match celebrations. Mathematics and science were conspicuous by their absence at the university.
See also: absence, by, conspicuous
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
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