Pin"na*cle (?), n. [OE. pinacle, F. pinacle, L. pinnaculum, fr. pinna pinnacle, feather. See Pin a peg.] 1. (Arch.) An architectural member, upright, and generally ending in a small spire, -- used to finish a buttress, to constitute a part in a proportion, as where pinnacles flank a gable or spire, and the like. Pinnacles may be considered primarily as added weight, where it is necessary to resist the thrust of an arch, etc.

Some renowned metropolis
With glistering spires and pinnacles around.

2. Anything resembling a pinnacle; a lofty peak; a pointed summit.

Three silent pinnacles of aged snow.

The slippery tops of human state,
The gilded pinnacles of fate.

Pin"na*cle, v. t. [imp. & p. p. Pinnacled (?); p. pr. & vb. n. Pinnacling (?).] To build or furnish with a pinnacle or pinnacles. T. Warton.