Etymograph

English

explainable

Explainable comes from Latin explanō ‘to flatten, spread out, make plain or clear,…’, from plānus ‘level, flat, even’, and ultimately from Proto-Indo-European *pleh₂-.

  1. Proto-Indo-Europeanc. 4500–2500 BCE*pleh₂-1‘flat’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*pl̥h₂nós1reconstructed
  3. Proto-Italicc. 1500–700 BCE*plānos1reconstructed
  4. Latinc. 75 BCE–200 CEplānus1‘level, flat, even’
  5. Latinc. 75 BCE–200 CEexplanō2‘to flatten, spread out, make plain or clear, explain’
  6. Englishtodayexplainable2

attested reconstructed ? uncertain or disputed deepest recorded ancestor

  1. 1 Wiktionary, Latin explano
  2. 2 Wiktionary, English explainable

Lineage

  1. Proto-Indo-Europeanc. 4500–2500 BCE*pleh₂-Wiktionary, Latin explano‘flat’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*pl̥h₂nósWiktionary, Latin explanoreconstructed
  3. Proto-Italicc. 1500–700 BCE*plānosWiktionary, Latin explanoreconstructed
  4. Latinc. 75 BCE–200 CEplānusWiktionary, Latin explano‘level, flat, even’
  5. Latinc. 75 BCE–200 CEexplanōWiktionary, English explainable‘to flatten, spread out, make plain or clear, explain’
  6. EnglishtodayexplainableWiktionary, English explainable

Formed from explain + -able

Latin plānus ‘level, plain’

Latin plānō ‘to flatten’

Latin explānō ‘to make plain, explain’

Old French explaner

Middle English explanen

English explain

Linked words

through Proto-Indo-European *pleh₂- ‘flat’

field, floor, planet, palm, clan, archipelago, fluke, parma, playa, placenta, flounder, palatine, placate, polonium, pelagic, plantar, lech, flay, veld, floe, purdah, implacable, planta, 48 more

through Proto-Italic *plānos

plane, planar, 13 more

through Latin plānus ‘level, flat, even’

plan, plain, llano, 15 more

through Latin explanō ‘to flatten, spread out, make plain or clear,…’

explanation, explanatory, esplanade, 5 more

Today it means

adj Able to be explained or understood

Sources

Sources: Wiktionary, “explainable”; the older steps come from the Wiktionary entry for Latin explano. 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 *pleh₂- / explainable