inflection vs inflect

inflection is a noun but inflect is not a noun.

Word	Noun	Adjective	Verb	Adverb
inflection	Yes	No	No	No
inflect	No	No	Yes	No

inflection (noun)	inflect (noun)
the patterns of stress and intonation in a language
a manner of speaking in which the loudness or pitch or tone of the voice is modified
deviation from a straight or normal course
a change in the form of a word (usually by adding a suffix) to indicate a change in its grammatical function

inflection (verb)	inflect (verb)
	vary the pitch of one's speech
	change the form of a word in accordance as required by the grammatical rules of the language