What it means
A tattletale is the one who runs to tell on everyone, the kid who informs the teacher the second a rule gets bent, the colleague who reports your two-minute late return from lunch. It's all about getting others in trouble to look good themselves, and nobody trusts a tattletale with a secret. Mostly a playground word, but the type never really grows out of it.
Usage examples
"Don't tell her, she's a tattletale and the whole class will know by recess."
"Nobody likes the office tattletale who clocks everyone's coffee breaks."
"Quit being a tattletale, it was one chip, not a federal crime."
"He'd smile in your face, then go full tattletale the second the teacher walked in."
Where it comes from
Built from tattle, meaning to blab or carry tales, plus tale. Tattletale shows up in American English from the 19th century as a schoolyard label for the kid who runs to an adult with everybody else's business. It stuck because the word sounds sing-songy, childish, and a bit mocking.
