Meaning of “inflection” - Learner’s Dictionary

inflection

noun [ C, U ] uk us /ɪnˈflekʃən/
WORD

the way the end of a word changes to show tense, plural forms, etc

VOICE

the way that your voice goes up and down when you speak, for example to show that you are asking a question

(Definition of “inflection” from the Cambridge Learner’s Dictionary © Cambridge University Press)