Definition of cosmic for English Language Learners. : 1  of or relating to the universe or outer space. : 2  relating to spiritual matters. : 3  very large or important.
Definition of boast. 1 : a statement expressing excessive pride in oneself : the act or an instance of boasting (see 2boast) : brag It may sound like a boast, but I truly am very wealthy.
Boast (verb). to vaunt one's self; to brag; to say or tell things which are intended to give others a high opinion of one's self or of things belonging to one's self; as, to boast of one's exploits courage, descent, wealth. Boast (verb). to speak in exulting language of another; to glory; to exult. Boast (verb).