Cycle stealing
A DMA mode in which the controller borrows the memory bus one cycle at a time, slowing the processor down a little instead of stopping it outright.
The alternative is burst or block mode, where the DMA controller grabs the bus and holds it until the whole block has moved. Faster, but the CPU sits idle meanwhile. With cycle stealing one word is moved, the bus is handed back, and the processor gets a few cycles before the next word. Intel's 8237 in the original PC called it single transfer mode; the technique is older than that and was common on 1960s minicomputers, where I/O would otherwise have eaten all of their meagre processor time.
The term also covers video chips that share memory with the CPU. The C64's VIC-II steals cycles on every bad line, and the Amiga's Agnus parcelled out the bus on a fixed timetable. Modern microcontrollers with a bus matrix avoid most of it, provided the CPU and the DMA happen to be using different memory banks.