Etymograph

English

clas

Clas comes from Welsh clas ‘cloister’, from Latin classis ‘any one of the five divisions into which…’, and ultimately from Proto-Indo-European *kelh₁- ‘to call, shout’.

  1. Proto-Indo-Europeanc. 4500–2500 BCE*kelh₁-1‘to call, shout’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*klh₁-d⁽ʰ⁾-ti-1‘a call’reconstructed
  3. Proto-Italicc. 1500–700 BCE*klāssis1reconstructed
  4. Latinc. 75 BCE–200 CEclassis2‘any one of the five divisions into which Servius Tullius divided the Roman citizenry’
  5. Proto-Brythonicc. 100 BCE–500 CE*klas2reconstructed
  6. Middle Welshc. 1150–1500clas2
  7. Welshc. 1500–presentclas2‘cloister’
  8. Englishtodayclas2

attested reconstructed ? uncertain or disputed deepest recorded ancestor

  1. 1 Wiktionary, Latin classis
  2. 2 Wiktionary, English clas

Lineage

  1. Proto-Indo-Europeanc. 4500–2500 BCE*kelh₁-Wiktionary, Latin classis‘to call, shout’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*klh₁-d⁽ʰ⁾-ti-Wiktionary, Latin classis‘a call’reconstructed
  3. Proto-Italicc. 1500–700 BCE*klāssisWiktionary, Latin classisreconstructed
  4. Latinc. 75 BCE–200 CEclassisWiktionary, English clas‘any one of the five divisions into which Servius Tullius divided the Roman citizenry’
  5. Proto-Brythonicc. 100 BCE–500 CE*klasWiktionary, English clasreconstructed
  6. Middle Welshc. 1150–1500clasWiktionary, English clas
  7. Welshc. 1500–presentclasWiktionary, English clas‘cloister’
  8. EnglishtodayclasWiktionary, English clas

Linked words

through Proto-Indo-European *kelh₁- ‘to call, shout’

low, hell, clear, calendar, claim, haul, reconciliation, declare, reconcile, claire, clarity, clarification, proclamation, squeal, reclamation, exclamation, clarinet, irreconcilable, clarion, claret, clamour, clamor, conciliar, ecclesial, ecclesiastic, 38 more

Today it means

noun A Celtic monastery

Sources

Sources: Wiktionary, “clas”; the older steps come from the Wiktionary entry for Latin classis. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.

Etymograph / Proto-Indo-European *kelh₁- / clas

Shirt and support for this word