forming ordinal numbers; in modern literary Eng. used with all simple numbers from fourth onward; representing OE. -þa, -þe, or -oða, -oðe, used with all ordinals except fífta, sixta, ellefta, twelfta, which had the ending -ta, -te; in Sc., north. Eng., and many midland dialects the latter, in form -t, is used with all simple numerals after third (fourt, fift, sixt, sevent, tent, hundert, etc.). In Kentish and O.Northumbrian those from seventh to tenth had formerly the ending -da, -de. All these variations, -th, -t, -d, represent an original Indo-Eur. -tos (cf. Gr. πέμπ-τος, L. quin-tus), understood to be identical with one of the suffixes of the superlative degree. In OE. fífta, sixta, the original t was retained, being protected by the preceding consonant; the -þa and -da were due to the position of the stress accent, according to Verner’s Law.
The ordinals from twentieth to ninetieth have -eth, OE. -oða, -oðe. In compound numerals -th is added only to the last, as 1/1345, the one thousand three hundred and forty-fifth part; in his one-and-twentieth year.
