thin person who eats a lot; big eater who stays thin
Describes someone who remains slim despite eating large amounts. Often used with a sense of surprise or admiration.
She's a big eater who stays thin, and always orders a large portion.
That person is a thin big eater, so no matter how much they eat, they don't gain weight.
痩せ型 is a neutral term for a slim body type, while 痩せの大食い is a set phrase highlighting the surprising combination of thinness and large appetite.
Standard kanji spelling for this set phrase.
Katakana spelling sometimes used for emphasis or in casual writing.
A set phrase combining 痩せ (thinness) and 大食い (big eater). The exact origin is uncertain, but it likely arose from the common observation that some thin people eat surprisingly large amounts.