pinnaculum

Latin

Etymology

From pinna (“plume, wing; parapet”). Pinnāculum appears in the Vulgate as a calque of Ancient Greek πτερύγιον (pterúgion, “pinnacle”), diminutive of πτέρυξ (ptérux, “wing”) (alternative translations of the Greek include fastīgium and pinna itself).[1] Therefore, the end of the word appears to be the neuter form of the Latin diminutive suffix -culus. However, pinnāculum is not a regularly formed diminutive: there is an irregular change of gender from the feminine base and an unexpected -ā- between the base and the suffix. The form may have been influenced by that of nouns ending in -āculum that were derived from the instrument noun suffix -culum: the Oxford English Dictionary suggests that the form pinnāculum was possibly based on analogy with prōpugnāculum (“bulwark, rampart”), from prōpugnō +‎ -culum.[2]

Pronunciation

(Classical) IPA^(key): /pinˈnaː.ku.lum/, [pɪnˈnäːkʊɫ̪ʊ̃ˑ]

(Ecclesiastical) IPA^(key): /pinˈna.ku.lum/, [pinˈnäːkulum]

Noun

pinnāculum n (genitive pinnāculī); second declension

(Late Latin) a peak, pinnacle

Declension

Second-declension noun (neuter).

Case	Singular	Plural
Nominative	pinnāculum	pinnācula
Genitive	pinnāculī	pinnāculōrum
Dative	pinnāculō	pinnāculīs
Accusative	pinnāculum	pinnācula
Ablative	pinnāculō	pinnāculīs
Vocative	pinnāculum	pinnācula

Descendants

→ English: pinnacle
→ French: pinacle
Italian: pennacchio (“plume”)
- → Middle French: pennache
  - French: panache
    - → English: panache
    - → Italian: panache
    - → Romanian: panaș
- → Portuguese: penacho
- → Spanish: penacho
Italian: pinnacolo (“pinnacle”) (probably borrowed), (possibly) pinnacolo (“pinochle”) (borrowing)
Old French: penail
→ Portuguese: pináculo
→ Spanish: pináculo

References

Burton, Philip (2002) The Old Latin Gospels: A Study of their Texts and Language, page 195
“pinnacle, n.”, in OED Online ⁠, Oxford, Oxfordshire: Oxford University Press, March 2022.