two by four

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Dimensional lumber

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two by four (plural two by fours)

1. (chiefly Canada, US) A length of sawn wood of cross section approximately 2 inches by 4 inches, most often employed as structural framing lumber (dimension or dimensional lumber).
   • 1959, Nat King Cole, Oh, Mary, don't you weep.:

     Well, Moses stood on the Red Sea shore, And smote the water with a two by four

   • Date debatable, Ledbelly - from a traditional folk song, Linin' Track

     Moses stood on the Red Sea shore, smotin' that water with a two by four

2. (chiefly Canada, US, dated) A small, modest building.
   • 1930, George, Ira Gershwin, But Not for Me:

     He'll plan a two by four/But not for me.

3. Alternative form of two-by-four (“kind of pornographic comic book”)

• clue-by-four

• four by two

• four by two, four-by-two