prot

. The radioactive chemical element, of atomic number 91; Atomic symbol Pa; at. wt. of longest-lived isotope, 231 (T1/2 = 32, 500 yrs.) Also called brevium, Uranium X2 and UX2. [ PJC ]

n. [ Proto- + Gr. 'agw`n a contest. See. Protagonist. So called because it was the first definitely ascertained principle of the brain. ] (Physiol. Chem.) A nitrogenous phosphorized principle found in brain tissue. By decomposition it yields neurine, fatty acids, and other bodies. [ 1913 Webster ]

n. [ Gr. prwtagonisth`s; prw^tos first + 'agonisth`s an actor, combatant, fr. 'agw`n a contest. ] One who takes the leading part in a drama; hence, one who takes lead in some great scene, enterprise, conflict, or the like. [ 1913 Webster ]

Shakespeare, the protagonist on the great of modern poetry. De Quincey. [ 1913 Webster ]

n. [ Gr. prw^tos first. ] (Physiol. Chem.) An amorphous nitrogenous substance found in the spermatic fluid of salmon. It is soluble in water, which an alkaline reaction, and unites with acids and metallic bases. [ 1913 Webster ]

a. [ Proto- + Gr. &unr_;, &unr_;, a man. ] (Zool.) Having male sexual organs while young, and female organs later in life. -- Pro*tan"trism n. [1913 Webster]

a. (Bot.) Proterandrous. [ 1913 Webster ]

‖n. [ L., fr. Gr. pro`tasis, fr. protei`nein to stretch before, forward; pro` before + tei`nein to stretch. ] 1. A proposition; a maxim. Johnson. [ 1913 Webster ]

2. (Gram.) The introductory or subordinate member of a sentence, generally of a conditional sentence; -- opposed to apodosis. See Apodosis. [ 1913 Webster ]

3. The first part of a drama, of a poem, or the like; the introduction; opposed to epitasis. B. Jonson. [ 1913 Webster ]

a. [ Gr. protatiko`s: cf. L. protaticus, F. protatique. ] Of or pertaining to the protasis of an ancient play; introductory. [ 1913 Webster ]