1590s, "pertaining to the clergy," from cleric + -al (1), or from French clérical, from Old French clerigal "learned," from Latin clericalis, from clericus (see cleric). Meaning "pertaining to clerks and copyists" is from 1798.
Clericalism "sacerdotalism, power or influence of the clergy" is from 1849. Clericality "quality of being clerical" is from 1650s.
clerical work
clerical collar
clerestory
clergy
clergyman
clergywoman
cleric
clerical
clerihew
clerisy
clerk
clerkly
clerkship