There is a song by MIA called "Jimmy" and she says a word repeatedly...?

Question

...it sounds phonetically like "acha". I think she is from India? Please excuse my ignornace if she is not. But what does 'acha' mean?

Answer 1

She is from Sri Lanka.

Answer 2

not srilanka, India.. she says "aaja" and not acha.

aaja means to come