ac ‧ cu ‧ mu ‧ la ‧ tor /əˈkjuːmjəleɪtə, əˈkjuːmjʊleɪtə $ -ər/ BrE AmE noun [countable]
1 . technical a part of a computer that stores numbers
2 . especially British English a kind of ↑ betting on the results of a series of horse races, by which any money you win from a race is bet on the next race