(slang) make a mistake.
an expression meaning to make a mistake in an otherwise correct procedure,
action, etc.; to
lose one's
reason or good sense. A
cogwheel is a
wheel that has teeth (called cogs) of hardwood or metal inserted between the teeth of another
wheel so that they mesh, thus when one
cogwheel is rotated, the other
wheel is turned as well. Through this arrangement, one can
transfer motion from one
wheel to the other
wheel. If one slips a
cogwheel, one or more of the cogs has not meshed properly into the other
wheel's cogs and the
wheel being driven by the other ceases to
turn until they realign.