a mirror (smooth reflecting surface) / Short for 鏡餅 (kagami mochi): a set of mochi rice cakes used in New Year celebrations / Short for 鏡物 (kagamimono):

mirror / speculum / pattern, model, example

a female given name / a surname

mirror

use one thing for many purposes / work someone hard

to use one's head

(geometry) spherical angle

everything

(colloquial) current boyfriend

(slang) Alternative form of 彼氏 (kareshi, “boyfriend”)