The word "welcher" is a noun that refers to someone who doesn’t repay a debt or does not fulfill a wager (a bet or agreement). It describes a person who takes advantage of others by not paying what they owe.
In more advanced discussions, you might use "welcher" in contexts where you discuss ethics in gambling or financial responsibility.
While "welcher" specifically refers to someone who swindles by not repaying debts or wagers, it is not commonly used in everyday English. It is more of a term you might find in literature or specific discussions about gambling or debts.
"To welch on a bet": This phrase means to not honor a bet.
"To stiff someone": This is an informal way to say that someone has not paid what they owe.