膨らむ

Etymology
First cited to the mid-800s.

From. The fukura portion is in turn from now-archaic verb, superseded by modern of the same meaning.

Verb

 * 1) to swell, to expand, to get bigger

Usage notes
The intransitive verb is used to describe something that happens naturally of its own accord, generally with a positive sense.



The synonym is used to describe something that happens due to an abnormality or external force, not necessarily with a positive sense.