A person who shows zeal (in various senses); esp. (in later use) one who ardently praises, supports, or promotes something.
Stressed as ˈzealer.
?a1450
Zele is double: þat is to sey gode & yuel. Gode zele is somtyme ytake for spousale luffyng... And so God, þat is þe spouse of holy chirche, is a strong zeler... Also þat God is a stronge zeler vengyng into þe 3. & þe 4. generacion.
in C. von Nolcken, Middle English Translation of Rosarium Theology (1979) 103
1557
Persecutours of euyil, zelers of good.
T. North, translation of A. de Guevara, Diall of Princesiii. xli. f. 219
1632
A feruent zealer of monasticall religion.
J. Porter, Flowers of Lives of Renowned Saincts 193
1673
Thou lover and zealer of Iesus.
R. Strange, translation of J. E. Nieremberg, Of Adoration in Spirit & Truthii. ix. 192
transferred and figurative. Applied to one who or that which in some way resembles or suggests a tiger. colloquial (chiefly Australian and New Zealand…