It is a Singlish slang in Singapore. Used to seem kind of fierce but can be used as a friendly term as well. Used when people call your name or ask you for help or a question. It is a hokkien word which translates to "What?" or "What do you want?"

The two states of being are as a human being, or a hungry ghost. Semi-regularly you need to ask yourself which you are. Sometimes it is human. Others, alas, it is hungry ghost.

The hungry ghost seeks validity outside of themselves. Someone pining for an indifferent ex is a hungry ghost. Someone who arrives alone at 6:30 on Saturday night to a pub is probably a hungry ghost. Obsessive checking of mobile phones, chat sites or networks are clear signs that one is a hungry ghost.

The best thing to do is just stay home and ride it out. Read a book. Find some good clean fun.