noun
Architectural term for a wooden piece used to support or brace another structural element.
この梁の下に受け木を入れて補強した。
We reinforced this beam by inserting a wooden support underneath.
支柱 is a general prop or strut, not necessarily wooden, while 受け木 specifically refers to a wooden support piece.
Compound of 受け (uke, 'receiving') + 木 (ki, 'wood'), literally 'receiving wood'.