Definitions

1. adjective

having a chubby or plump body; stout

“He was a bit of a tubby kid, but he was full of energy.”

2. noun

a round or plump person

“The comedian made jokes about the tubby guy who couldn’t fit into the tiny car.”

3. verb

to make or become chubby or plump

“After eating too many sweets, she started to tubby up and had to change her diet.”