from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A copper-containing enzyme of plant and animal tissues that catalyzes the production of melanin and other pigments from tyrosine by oxidation, as in the blackening of a peeled or sliced potato exposed to air.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An enzyme, similar to catechol oxidase, that catalyzes the production of phenolic pigments such as melanin.
from The Century Dictionary and Cyclopedia
- n. An oxidizing ferment which acts upon tyrosin and leads to the formation of various black substances which are known only in part. The formation of homogentisic acid (alkapton) is probably referable to a tyrosinase. The black pigment secreted by the octopus is produced in this manner.
tyrosine + -ase (Wiktionary)