To distort or collapse under physical pressure; especially, of a slender structure in compression.
To make bend; to cause to become distorted.
To give in; to react suddenly or adversely to stress or pressure (of a person).
It is amazing that he has never buckled after so many years of doing such urgent work.
To yield; to give way; to cease opposing.
To enter upon some labour or contest; to join in close fight; to contend.
To buckle down; to apply oneself.
To fasten using a buckle.
To unite in marriage.