smother vs bottle up

smother is a noun but bottle up is not a noun.

Word	Noun	Adjective	Verb	Adverb
smother	Yes	No	Yes	No
bottle up	No	No	Yes	No

As verbs, bottle up is a hypernym of smother; that is, bottle up is a word with a broader meaning than smother:

smother: suppress in order to conceal or hide
bottle up: consciously restrain from showing; of emotions, desires, impulses, or behavior

Other hypernyms of smother include inhibit, suppress.

smother (noun)	bottle up (noun)
a stifling cloud of smoke
a confused multitude of things

smother (verb)	bottle up (verb)
deprive of oxygen and prevent from breathing	consciously restrain from showing; of emotions, desires, impulses, or behavior
suppress in order to conceal or hide
envelop completely
deprive of the oxygen necessary for combustion
form an impenetrable cover over