A B C D E f G H I L N O P Q R S T u V W X
A- Ac Ad Al On ace Ouch

Abbreviation of "Automatic Call Distribution", translated "automatic call forwarding“. Using ACD, the phone number of the caller identified in order to route the call to the appropriate call recipient according to priority.
See also call forwarding when busy (CFB), call forwarding on no reply (CFNR), unconditional call forwarding (CFU).