convention vs convening

convention and convening both are nouns.

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

As nouns, convention and convening are synonyms defined as:

convention (noun)	convening (noun)
the act of convening	the act of convening
orthodoxy as a consequence of being conventional
something regarded as a normative example
(diplomacy) an international agreement
a large formal assembly