As a Noun:
1. A long, thin reptile with no legs. English = snake.
2. A person who says nasty things about other people. English = bitch.
As a Verb or Adjective:
1. Of a snake, to flick out its forked tongue (usually while making a sound). English = hiss.
2. Of a person, to say nasty things about other people. English = bitch.
3. Of a person, to behave in a way that is rude and offensive, particularly by saying nasty things about other people. English = (be) bitchy.
Note:
1. A common variant of this sign has the fingers extended all the time, with the whole hand moved away twice in a poking action. (This form appears particularly frequent in the Northern Territory, especially in the Darwin area.)