Combination is a set or series of different actions, colors or sounds put together.
"man did you see that combo i nailed to his face? left jab, right jab and hook!"
"that classic violin goes nice with that beatboxing, seems that combo from the past and future works nice"
Sally: Dude I just did a 3 hit combo on your face!
Jeff: Yeah but it only did 10 damage.
Sally: But you only have 5 hp!