1Consisting of only one part, element, or unit; single; = "onefold". Now rare (Scottish and Irish English after Middle English).
2Free from duplicity; sincere, honest, faithful; plain, straightforward. Scottish after Middle English.
Old English; earliest use found in Laws of Aelfred. Cognate with or formed similarly to Old Frisian ēnfald, Old Saxon ēnfāld (Middle Low German ēnvōlt), Old High German einfalt, Old Icelandic einfaldr, Gothic ainfalþs from the Germanic base of one + the Germanic base of -fold.