Letters that make well up
e, l, p, u, w are letters that make 'well up'
swell up is a word created by adding a letter to 'well up'
1 possible definitions for 'well up'
Under this definition, well up is a verb and has the following properties:
swell has the same meaning as well up
'well up' can be a type of uprise, originate, spring up, develop, arise, rise, grow.