/ ˈnɑːsɪsɪzəm; NAmE ˈnɑːrs-/ noun
[ U ] ( formal , disapproving ) the habit of admiring yourself too much, especially your appearance
► nar·cis·sis·tic / ˌnɑːsɪˈsɪstɪk; NAmE ˌnɑːrs-/ adjective
ORIGIN
From the Greek myth in which Narcissus , a beautiful young man, fell in love with his own reflection in a pool. He died and was changed into the flower which bears his name.