Pelching (or to pelch) is an unfortunate side affect of people who have failed to mature mentally. It is the act of trying to reverse actions taken in a game done by one who cannot fathom the concepts of losing or fair play.
Sylvia: Knight to queen's rook.
Andy: Hey, I didn't see that or I wouldn't have moved my pawn. Give me back by rook.
Sylvia: Hey, no pelching!
A term that can now not only be used to describe someone bitching at ya and telling you what to do but also to describe something that is great or chill or cool or dope or whatever... so yeah, preach on.
person 1: I just bought a dope cruiser bike at the thrift store so now im set for the summer
(VERB) To consume alcohol, generally a large amount, at one's own place of residence or that of a friend, as a precursor to going out to a party, bar or club. Also 'prelash'(NOUN). Can be practised alone or in groups. Often performed at the same time as getting changed, putting on make up or straightening hair. Favourite pastime of students. Can involve drinking games such as 'Ring of Fire.' Generally considered to be a cheap, convenient alternative to drinking in bars before clubs open.