English
unexplainable
Unexplainable comes from Latin explanō ‘to flatten, spread out, make plain or clear,…’, from plānus ‘level, flat, even’, and ultimately from Proto-Indo-European *pleh₂-.
- Proto-Indo-Europeanc. 4500–2500 BCE*pleh₂-1‘flat’reconstructed
- Proto-Indo-Europeanc. 4500–2500 BCE*pl̥h₂nós1reconstructed
- Proto-Italicc. 1500–700 BCE*plānos1reconstructed
- Latinc. 75 BCE–200 CEplānus1‘level, flat, even’
- Latinc. 75 BCE–200 CEexplanō2‘to flatten, spread out, make plain or clear, explain’
- Englishtodayunexplainable2
attested reconstructed ? uncertain or disputed deepest recorded ancestor
- 1 Wiktionary, Latin explano
- 2 Wiktionary, English unexplainable
Lineage
- Proto-Indo-Europeanc. 4500–2500 BCE*pleh₂-Wiktionary, Latin explano‘flat’reconstructed
- Proto-Indo-Europeanc. 4500–2500 BCE*pl̥h₂nósWiktionary, Latin explanoreconstructed
- Proto-Italicc. 1500–700 BCE*plānosWiktionary, Latin explanoreconstructed
- Latinc. 75 BCE–200 CEplānusWiktionary, Latin explano‘level, flat, even’
- Latinc. 75 BCE–200 CEexplanōWiktionary, English unexplainable‘to flatten, spread out, make plain or clear, explain’
- EnglishtodayunexplainableWiktionary, English unexplainable
Linked words
through Proto-Indo-European *pleh₂- ‘flat’
field, floor, planet, palm, clan, archipelago, fluke, parma, playa, placenta, flounder, placate, pelagic, polonium, palatine, plantar, lech, flay, veld, floe, purdah, implacable, planta, 47 more
through Proto-Italic *plānos
through Latin plānus ‘level, flat, even’
through Latin explanō ‘to flatten, spread out, make plain or clear,…’
Today it means
adj That doesn't have a known or readily available explanation.
Sources
Sources: Wiktionary, “unexplainable”; 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- / unexplainable