The Jargon File, Version 4.2.2…
“ A register being used for arithmetic or logic (as opposed to addressing or a loop index) , especially one being used to accumulate a sum or count of many items. This use is in context of a particular routine or stretch of code. "The FOOBAZ routine uses A3 as an accumulator." 3. One's in-basket (esp. among old-timers who might use sense 1) . "You want this reviewed? Sure, just put it in the accumulator." (See stack.) Node:ACK, Next:Acme, Previous:accumulator, Up:= A = ACK /ak/ interj. ”
