1 C1 informal
(Non-standard, rare) To become slimmer or thinner in body.
"He seemed to have thinned up considerably since the last time we met."
thin up
C1 informal intransitive
A rare and non-standard variant meaning to become thinner or to thin something upward; not widely used in standard English.
In plain English
To become thinner (not a common phrase — most people say 'thin out' or 'slim down' instead).
What does "thin up" mean?
One main meaning — here's how to use it.
Literal vs figurative
Words literally mean
To become thinner moving upward.
Actually means
To become thinner (not a common phrase — most people say 'thin out' or 'slim down' instead).
Usage tip
This phrasal verb is not standard and is rarely found in mainstream English usage. Learners are advised to use 'thin out', 'slim down', or 'lose weight' instead. May appear in very informal or dialectal speech.
How to conjugate "thin up"
The five tense forms you'll use most often.
Base
thin up
I/you/we/they
3rd person
thins up
he/she/it
Past simple
thined up
yesterday
Past participle
thined up
have + pp
-ing form
thining up
continuous
Hear "thin up" in the wild
Listen to native speakers using "thin up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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