gam ‧ bling /ˈɡæmblɪŋ/ BrE AmE noun [uncountable]
when people risk money or possessions on the result of something which is not certain, such as a card game or a horse race ⇨ betting :
The lottery is probably the most popular form of gambling.
gambling debts
The police raided a number of illegal gambling dens (=places for illegal gambling) .