Now only Hist. See also TERTIA. [a. Sp. tercio (Minsheu), obs. It. tertio (Florio), mod.It. terzo, Pg. terço a regiment:—L. tertium a third.] orig. A regiment of the Spanish infantry of the 16–17th c.; applied also to the Italian forces of that period; hence, A body of foot forming a main division of an army.
1583. Stocker, Civ. Warres Lowe C., II. 65. Hee … sent thether Sardigne his Regiment or Tertio, with the Maister of his Campe, and three Ensignes of the Regiment or Tertio of Lombardes.
1590. Sir J. Smyth, Disc. Weapons, 10 b. A Tercio is not to bee holden for compleate of anie smaller number than of 3000. soldiers.
1598. Barret, Theor. Warres, 15. The Campe is deuided into sundry Tertios or Regiments.
1622. F. Markham, Bk. War, V. i. 161. The Colonell of a Foot-Regiment … amongst the old Romans … commanded a Tertio or Regiment.
1904. Edin. Rev., July, 116. The deep formation in solid squares—that of the renowned tercios—was still dominant.
