1 þriðjungr
m. the third part of a thing, Nj. 3, Eg. 57, 266, Fms. i. 70, N. G. L. i. 421, Grág. i. 156, passim.
2 þriðjungr
II. as a political division, the third part of a shire, A. S. Þrithing, low Lat. Trithinga, a Thriding (cp. the Yorkshire Ridings); in Icel. every þing (q. v.) was subdivided into three parts (i. e. there were three ‘godords’ in each þing); þriðjungs-maðr, an inmate or liegeman of such a ‘riding,’ Grág. i. 16; þriðjungs vist, domicile in a ‘riding’ (referring to the þingfesti, q. v.), 114: in Norway a church-division, fjórðungs menn eða þriðjungs, N. G. L. i. 133.
3 þriðjungr
COMPDS: þriðjungsauki, þriðjungarfé, þriðjungafélag, þriðjungskona, þriðjungspenningr, þriðjungaskipti, þriðjungstíund, þriðjungsþing.