IPA: /ˈkæl.aʊt/
KK: /ˈkælˌaʊt/
A callout is a specific mention or invitation to someone, often used to highlight important information or to challenge someone to a competition.
The teacher made a callout to the student who answered the question correctly.
Callout → It is formed from "call" (from Old English *ceallian*, meaning to cry out or shout) and "out" (meaning outside or outward). The word "callout" refers to the act of calling out or shouting something to someone, often in a public or noticeable manner.
Think of someone 'crying out' ('call') to someone 'outside' ('out') — that's why callout means to shout something out.