Lewis & Short

sextŭla, ae, f. (sc. pars) dim. [sextus], the sixth part of an uncia, and, accordingly, the seventy-second part of an as (v. as), Varr. L. L. 5, § 171 Müll.; Rhemn. Fann. Pond. 22: facit heredem ex duabus sextulis M. Fulcinium, etc., Cic. Caecin. 6, 17.
As a land measure, Col. 5, 1, 9; 5, 2, 2.