English
theirself
From their + -self, patterned on e.g.
Formed from their + -self
Proto-Germanic *þaizǭ ‘genitive plural of *sa ‘that’’
Proto-Norse þaizō
Old Norse þeira ‘of them’
English their
Today it means
pron —
Sources
Sources: Wiktionary, “theirself”. 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 / theirself