telly vs boob tube

telly and boob tube both are nouns.

Word	Noun	Adjective	Verb	Adverb
telly	Yes	No	No	No
boob tube	Yes	No	No	No

As nouns, telly and boob tube are synonyms defined as:

telly and boob tube: an electronic device that receives television signals and displays them on a screen

Other synonyms of telly include goggle box, idiot box, television, television receiver, television set, tv, tv set.

telly (noun)	boob tube (noun)
an electronic device that receives television signals and displays them on a screen	an electronic device that receives television signals and displays them on a screen