To "be a man about it"; to do the things a man is traditionally expected to do, such as taking responsibility for the consequences of one's actions; displaying bravery or toughness in the face of danger, adversity, or a challenge; providing for one's family, etc. (Compare man (“brace oneself, steel oneself”).)
To vigorously guard the opponent to whom one is assigned.
(Of personnel) to assemble, each person manning (attending to) his station, prepared for the departure of an aircraft, ship, etc. (Compare man (“supply with staff; take up position to operate”).)
To staff adequately; to staff up; to successfully fill all needed labor positions. (Compare man (“supply with staff”).)
To put up with something; to deal with something, such as pain or misfortune, without complaining.