noun
MountaineeringAn act of wedging an open hand in a crack as a handhold.
Origin
1940s. From hand + jam.
verb
Mountaineering1To climb by using a hand jam or hand jams. With up, over, etc.
2To wedge an open hand in (a crack) as a handhold.
Origin
1960s; earliest use found in Punch. From hand + jam, after hand jam.
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