lick (someone's) arse
vulgar To flatter, fawn over, or eagerly agree with (someone, especially a person of higher authority) as a means of currying favor. Primarily heard in UK, Ireland. It's no wonder you're the teacher's favourite from the way you lick her arse!
lick (someone's) ass
vulgar To flatter, fawn over, or eagerly agree with (someone, especially a person of higher authority) as a means of currying favor. Primarily heard in US. It's no wonder you're the teacher's favorite from the way you lick her ass! Look, it's just the nature of this business that sometimes you have to lick ass if you want to get ahead.
lick my arse
1. vulgar slang An exclamation of contempt, disregard, or general disrespect. Primarily heard in UK. Lick my arse, Jerry! You couldn't do a better job fixing this truck if your life depended on it! Some guy tried hitting on me at the bar, so I told him to lick my arse, and I walked off!
2. vulgar slang An expression of refusal to do something someone has requested. Primarily heard in UK. You want me to start working on Saturdays, too? Well you can lick my arse, I don't need this job!