jamb /jam, dʒæm 
/ ▸ noun a side post or surface of a doorway, window, or fireplace: he leaned against the door jamb.
▪ a columnar mass or pillar in a mine or quarry.
– ORIGIN Middle English : from Old French jambe ‘leg, vertical support’, based on Greek kampē ‘joint’.
EnglishOxford New American Dictionary
