To inflect means to change the form of a word to show different grammatical uses, like tense, number, or possession. When you add -ed to “walk” to make “walked,” you're inflecting the verb to show past tense. When you change “child” to “children,” you're inflecting the noun to show plural.

English inflects words in fairly simple ways compared to many languages. We add -s for plurals, -ing for ongoing actions, and -er for comparisons. But some words inflect irregularly: “go” becomes “went,” not “goed.” Learning these irregular inflections is one of the trickier parts of mastering English.

The word also means to change the pitch or tone of your voice while speaking. When you ask a question, your voice naturally inflects upward at the end. When you read a story aloud with expression, you inflect your voice to show excitement, sadness, or surprise. A monotone speaker never inflects their voice, making everything sound flat and boring. Teachers often remind students to inflect their voices during presentations so the audience stays engaged.