1. Architecture A small turret or spire on a roof or buttress.
2. A tall pointed formation, such as a mountain peak.
3. The highest point; the culmination. See Synonyms at summit.
tr.v. pin·na·cled, pin·na·cling, pin·na·cles
1. To furnish with a pinnacle.
2. To place on or as if on a pinnacle.
[Middle English, from Old French, from Late Latin pinnāculum, diminutive of Latin pinna, feather; see pet- in the Appendix of Indo-European roots.]
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