Radio slang acknowledgement, meaning "i heard you" or "I understand." Synonymous with "Roger." Often shortened to "copy."
-Sir, we're aout to drop nuclear payload. Shall we proceed, over?
-Negative, you're to return to base immediately! We've got a sandstorm headed your way! Over.
-Repeat, that is a negative, return to base immediately. Do you copy?
-Copy that, HQ. Returning to base.