byproduct

Noun

by-product (plural by-products)

1. Something made incidentally during the production of something else.
   • It was about this time that the first experiments were made (in Germany) with basic slag, a material which had hitherto been regarded as a worthless by-product of steel manufacture. A year or two later field trials were begun in England, with the final result that basic slag has become recognized...1911, “History of English Agriculture”, in 1911 Encyclopædia Britannica
2. A consequence, especially a side effect.
   • The many Indian restaurants all over Britain are a by-product of the large waves of immigration from the subcontinent.