The definition of a chancer is a British term for someone who takes advantage of situations and manipulates them to his own benefit.
An example of a chancer is someone who swoops in and buys a painting from a little old lady when he knows it is a Picasso and she doesn't.
Brit., Informal a reckless, improvident, often somewhat unscrupulous opportunist
Origin of chancer; from chance () + -er
- (British slang) An opportunist