To make a clicking noise similar to the movement of the hands in an analog clock.
To make a tick or checkmark.
To work or operate, especially mechanically.
He took the computer apart to see how it ticked.
To strike gently; to pat.
To add a bird to a list of birds that have been seen (or heard).
To go on trust, or credit.
To give tick; to trust.
Ticked off; annoyed.