OK, you be the ump.

       Sounds have characteristics that can help a word into its meaning.  Consider the abruptness and curtness of these short words ending with a flat mid vowel, closed mouth nasal, and dead stop plosive.

       bump
       sump
       rump
       chump
       mump(s)
       lump
       hump
       jump
       dump
       grump
       Trump