(n)guardthe person who lines up between the center and the tackles on the offensive line of a football team on the line of scrimmage“the left guard was injured on the play”
(n)precaution, safeguard, guarda precautionary measure warding off impending danger or damage or injury etc.“he put an ice pack on the injury as a precaution”, “an insurance policy is a good safeguard”, “we let our guard down”