niggle
(noun, verb)
noun
1. A minor complaint or problem.
2. (obsolete) Small, cramped handwriting.
verb
1. worry unnecessarily or excessively
Similar word(s): fret, fuss
Definition categories: emotion, worry
2. argue over petty things
Similar word(s): bicker, brabble, pettifog, quibble, squabble
Definition categories: communication, argue, contend, debate, fence