A brief excursion or attempt, especially outside one's accustomed sphere.
A sudden or irregular incursion in border warfare; hence, any irregular incursion for war or spoils; a raid.
To participate in a foray.
To do or attempt something outside one's typical area of expertise.
To keep safe; to defend; to guard; to prevent harm coming to.
To book a passenger on a later flight if there is a chance they will not be able to board their earlier reserved flight.