1. To deliberately embarrass, trick, or make fun of someone because it amuses you. English = tease.
2. To speak offensively to someone about their weaknesses or failures in order to upset or annoy them. English = taunt.
3. To make someone appear foolish, for example by saying something funny about them. English = mock, ridicule, torment. Idiomatic English = poke fun at, get at.
4. To keep doing something to someone that annoys or bothers them, especially saying unkind things. English = pester, harass.