1.NounAn animal, such as a dairy cow, kept for the milk it produces.
2.NounA person who milks.
"The milker woke up at dawn each day to tend to the cows.; The snake milker massages the glands to extract the full measure of venom during each milking."
3.NounA milking machine.
4.NounA conservative poker player who only raises the stakes on a good hand.