quibble

Short definition from Wiktionary

Noun

1. 1
   An argument or objection based on an ambiguity of wording or similar trivial circumstance; a minor complaint.
2. 2
   A pun.

Verb

1. 1
   To complain or argue in a trivial or petty manner.
2. 2
   To contest, especially some trivial issue in a petty manner.