four by two

noun3

1. •
   (UK, Australia) A length of sawn wood of cross section 4 inches by 2 inches, most often employed as structural framing lumber / timber.

   • She would sit here sometimes, perched on a bag of concrete looking at the big lumps of four by two and imagining what she might do with them if she had a chance. — 1994
2. •
   (slang) A Jew.
3. •
   (UK, Australia) A cotton cloth 4 inches wide with lines two inches apart, conveniently torn into two inch lengths for cleaning a rifle barrel using a pull through.