holding an erroneous opinion of oneself, one's own effort, or the like.
2.
being mistaken, forming an erroneous judgment, etc., in one's own mind, as from careless or wishful thinking: If you thought my friendship was love, you were self-deceived.
a screen or mat covered with a dark material for shielding a camera lens from excess light or glare.
a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question.