Etymology Dictionary

BUTTRESS,  a support; in architecture.  (F.)   Bale uses butrasse in the sense of a support; Apology, p. 155.   α. The word is commonly explained from the F. bouter, to support.   Cotgrave has:  'Boutant, m. a buttress, or shorepost.'   Thus all etymologists have failed to account for the ending -ress.   β. The truth is rather that buttress is a modification of the O.F. bretesche (bretesque in Cotgrave), once much in use in various senses connected with fortification; such as a stockade, a wooden outwork, a battlement, portal for defence, &c.   This word, being used in the sense of 'battlement,' was easily corrupted into that of 'support' by referring it to the F. bouter, the verb to which it was indebted for its present form and meaning.   B. The above suggestion is fairly proved by a passage in P. Plowman, A. vi. 79, or B. v. 598, where the word boterased occurs as a past participle, with the sense of 'fortified,' or 'embattled,' or 'supported;' spoken of a fort.   The various readings include the forms brutaget, briteschid, and bretaskid, clearly shewing that confusion or identity existed between a buttress and a bretesche.   The O.F. bretesche appears in Low Latin as brestachia, bretagia, breteschia, &c.   The Provençal form is bertresca, the Italian is bertesca.   As to the etymology of this strange word, Diez wisely gives it up.  The G. brett, a plank, may begin the word; but the termination is unknown. [※]

ADDENDA

BUTTRESS,  (F.,—M.H.G.)   Palsgrave has the forms bottras and butteras.   The derivation from F. bouter, to thrust, is now known to be the correct one.   Wedgwood rightly says:—'If Godefroy's [O.F.] Dict. had been published a little earlier, Skeat would probably not have offered this very unsatisfactory etymology [which identifies the word with brattice].   We there find bouteret, buteret (of an arch or pillar), thrusting, bearing a thrust.   Et y a vi. ars bouterez en maniere de pillers qui boutent contre le siege du hannap; Inv. du Duc d'Anjou, 1360.   Les ars bouterez (i.e. arcs-boutants, flying buttresses) sont mis trop haut; Reg. des délib. du Chap. de Troyes, 1362.   Deux pilliers bouterez, 1358.   Soubbassement avec plusseurs bouteretz, with many buttresses; 1504.'   It thus appears that buttress = bouterets, and is really a plural!   The F. pl. suffix -ez or -ets was mistaken, in English, for the commoner F. suffix -esse, Eng. -ess.   Buttress is, in fact, a mistake for buttrets, and the word should have been, in the singular, buttret.   The confusion was due to the ambiguous value of the F. z, which properly stood for ts, but was often considered as being merely a voiced s.   We find the further corruption butterace, pl. butteraces, in the Will of Hen. VI.; Nichols, Royal Wills, pp. 295, 302; but at p. 303, in the same Will, buttrace is a pl. form.   So also Palsgrave uses butteras as a pl. sb., where he says::  'I butteras a buyldyng, I underset it with butteras to make it stronger.'