inflection

(n) - If a word inflects, its form changes according to its meaning or use. So, an inflection can be the way the sound of your voice goes up and down when you are speaking. It can also be the way in which a word changes its form to show a difference in its meaning or use (like when you a suffix such as -s, -es, -ed, or -ing).

• Synonyms: accent, intonation, pitch, change, variation, morphology
• Antonyms: monotone
• Etymology: Early 15th Century Latin, from in- meaing "in" + flectere meaning "to bend" (as in flexible)
• Morphology: inflected, inflect
• Example: How can your voice inflection change the meaning of a sentence?

Here is a great game to help us learn about Order of Operations math today (notice the inflection...):