膨れる

Etymology
From, following , from.

Compare, , and , from the way a bag is filled with items.

First cited to the , completed sometime after 759.

Verb

 * 1) to swell, to expand

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

Its synonym, the intransitive verb is used to describe something that happens naturally of its own accord, generally with a positive sense.