14 letters · 17 points in Scrabble
adjective operating or moving or allowing movement in one direction only
originEtymology tree Proto-Indo-European *ís? Proto-Indo-European *h₁óynos Proto-Italic *oinos Old Latin oinos Latin ūnus Latin ūni-der. English uni- English directional English unidirectional From uni- + directional.
Etymology from Wiktionary, CC BY-SA 3.0