pettiest
pet-ti-est
adjective
The superlative form of 'petty', meaning most trivial, unimportant, or mean-spirited.
"That was the pettiest complaint I've ever heard."
Thesaurus
Synonyms: narrow, petty, narrow-minded, small-minded, piddling, trivial, little, fiddling, unimportant, footling, niggling, piffling
Antonyms: grand larceny, grand theft