Opp [ɒp] — (short for opponent) is an enemy or competitor, som | WTF English

Opp [ɒp] — (short for opponent) is an enemy or competitor, someone who is working against you in some way (скорочено від «опонент») — це ворог або конкурент, хтось, хто якось працює проти вас).

The next time you deny your teen's request for cash or an outing on a school night, you might find yourself in the opp category.