practice vs convention

practice and convention both are nouns.

Word	Noun	Adjective	Verb	Adverb
practice	Yes	No	Yes	No
convention	Yes	No	No	No

As nouns, convention is a hyponym of practice; that is, convention is a word with a more specific, narrower meaning than practice:

Other hyponyms of practice include custom, tradition, formula, normal, pattern, rule, heritage.

practice (noun)	convention (noun)
a customary way of operation or behavior	the act of convening
systematic training by multiple repetitions	orthodoxy as a consequence of being conventional
the exercise of a profession	something regarded as a normative example
translating an idea into action	(diplomacy) an international agreement
knowledge of how something is usually done	a large formal assembly

practice (verb)	convention (verb)
learn by repetition
engage in a rehearsal (of)
carry out or practice; as of jobs and professions
avail oneself to
engage in or perform