Etymograph

English

thro

Thro comes from Old Norse þrár ‘stubborn, obstinate, persevering’, and goes back to Proto-Indo-European *ter- ‘to grind, drill, turn’.

  1. Proto-Indo-Europeanc. 4500–2500 BCE*ter-1‘to grind, drill, turn’reconstructed
  2. Proto-Germanicc. 500 BCE–200 CE*þrawaz1‘obstinate’reconstructed
  3. Old Norsec. 800–1350þrár1‘stubborn, obstinate, persevering’
  4. Middle Englishc. 1150–1500thro1
  5. Englishtodaythro1

attested reconstructed ? uncertain or disputed deepest recorded ancestor

  1. 1 Wiktionary, English thro

Lineage

  1. Proto-Indo-Europeanc. 4500–2500 BCE*ter-Wiktionary, English thro‘to grind, drill, turn’reconstructed
  2. Proto-Germanicc. 500 BCE–200 CE*þrawazWiktionary, English thro‘obstinate’reconstructed
  3. Old Norsec. 800–1350þrárWiktionary, English thro‘stubborn, obstinate, persevering’
  4. Middle Englishc. 1150–1500throWiktionary, English thro
  5. EnglishtodaythroWiktionary, English thro

Linked words

through Proto-Indo-European *ter- ‘to grind, drill, turn’

term, tram, intrigue, treachery, thrill, inextricable, 35 more

Today it means

adj Eager; earnest; vehement.

Sources

Sources: Wiktionary, “thro”. 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 *ter- / thro

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