We found 12 dictionaries that define the word by-products:

General (7 matching dictionaries)

1. by-products: Merriam-Webster
2. by-products, by-products: Collins English Dictionary
3. By-Products, By-products, by-products: Wordnik
4. by-products: Wiktionary
5. by-products: Dictionary.com
6. By-products: Wikipedia, the Free Encyclopedia
7. by-products: TheFreeDictionary.com

Business (3 matching dictionaries)

8. BY-PRODUCTS: Accounting Glossary
9. by-products: Legal dictionary
10. Accounting, Business Studies and Economics Dictionary (No longer online)

Computing (1 matching dictionary)

11. by-products: Encyclopedia

Medicine (1 matching dictionary)

12. by-products: Medical dictionary

(Note: See by-product as well.)

Definitions from WordNet (by-product) ▸ noun:  a product made during the manufacture of something else ▸ noun:  a secondary and sometimes unexpected consequence ▸ Also see by-product ▸ Words similar to by-products ▸ Usage examples for by-products ▸ Idioms related to by-products ▸ Wikipedia articles (New!) ▸ Popular adjectives describing by-products ▸ Words that often appear near by-products ▸ Rhymes of by-products ▸ Invented words related to by-products