c. 1300, atiren, "to fit out, equip; to dress in finery, to adorn," from Old French atirer, earlier atirier "to equip, ready, prepare," from a- "to" (see ad-) + tire "order, row, dress" (see tier). Related: Attired; attiring.
c. 1300, "equipment of a man-at-arms; apparel, dress, clothes," from attire (v.).
word-forming element expressing direction toward or in addition to, from Latin ad "to, toward" in space or time; "with regard to, in relation to," as a prefix, sometimes merely emphatic, from PIE root *ad- "to, near, at."
Simplified to a- before sc-, sp- and st-; modified to ac- before many consonants and then re-spelled af-, ag-, al-, etc., in conformity with the following consonant (as in affection, aggression). Also compare ap- (1).
In Old French, reduced to a- in all cases (an evolution already underway in Merovingian Latin), but written forms in French were refashioned after Latin in 14c. and English did likewise 15c. in words it had picked up from Old French. In many cases pronunciation followed the shift. Over-correction at the end of the Middle Ages in French and then English "restored" the -d- or a doubled consonant to some words that never had it (accursed, afford). The process went further in England than in France, where the vernacular sometimes resisted the pedantic, resulting in English adjourn, advance, address, advertisement (Modern French ajourner, avancer, adresser, avertissement). In modern word-formation sometimes ad- and ab- are regarded as opposites, but this was not in classical Latin.
late 15c., "iron plates forming a rim of a carriage wheel," probably from tire "equipment, dress, covering" (c. 1300), a shortened form of attire (n.). The notion is of the tire as the dressing of the wheel. The original spelling was tyre, which had shifted to tire in 17c.-18c., but since early 19c. tyre has been revived in Great Britain and become standard there. Rubber ones, for bicycles (later automobiles) are from 1877. A tire-iron originally was one of the iron plates; as a device for separating a tire from a wheel, by 1909.
<a href="https://www.etymonline.com/word/attire">Etymology of attire by etymonline</a>
Harper, D. (n.d.). Etymology of attire. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/attire