"ornament at the top of a spire, gable, etc.," mid-15c., from fyniall "putting an end to, binding" (early 15c.), a variant of final.
Entries linking to finial
final adj.
early 14c., from Old French final "final, last," and directly from Late Latin finalis "of or pertaining to an end, concluding, final," from finis "end" (see finish (v.)). As a noun, late 14c., "that which comes last;" meaning "final contest" in a sporting sense is from 1880. As a shortening of final examination, from 1880.