from The Century Dictionary and Cyclopedia
- n. Something beside the principal matter; something incidental.
Sorry, no etymologies found.
That the latter manner of search (which is all) they pass over compendiously and slightly as a by-matter.
I knew one that, when he wrote a letter, he would put that which was most material in the postscript, as if it had been a by-matter.
Inwardly ashamed of my loose methods, compared with Rand's thorough ones, I hastened to ask of Mr. Steele, as a by-matter, being sure that he would know.