12 letters · 17 points in Scrabble
adjective following accepted customs and proprieties
adjective conforming with accepted standards
adjective (weapons) using energy for propulsion or destruction that is not nuclear energy
originEtymology tree English convention Proto-Indo-European *h₂el-der.? Proto-Italic *-ālis Latin -ālisbor. Old French -albor. ▲ Latin -ālis Old French -elbor. ▲ Latin -ālisbor. Middle English -al English -al English conventional From convention + -al.
Etymology from Wiktionary, CC BY-SA 3.0