protagon

English

Etymology

From proto- +‎ Ancient Greek ἀγών (agṓn, “a contest”). See protagonist. So called because it was the first definitely ascertained principle of the brain.

Noun

protagon (countable and uncountable, plural protagons)

1. (biochemistry) A nitrogenous phosphorized principle found in brain tissue. By decomposition it yields neurine, fatty acids, and other bodies.

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for “protagon”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.)