thrittithe

• threttiþe, þritteþe, þrittiþ, þrittiþe
• threttydde, þrettyde (East Anglia); þrittide (East Saxon); þrittaȝte (Kent)
• thryddyþ, thrydtythe (Southern, West Midland)
• þrituðe, þrittuðe (Early Middle English, West Midland)
• thrittyde (Northern) thretyd, threttyd (Early Scots)

Inherited from Old English þrītigoþa, þrittigoþa; equivalent to thritty (“thirty”) +‎ -the (ordinal suffix).

Kentish þrittaȝte is from Kentish Old English þrītiogoþa, with devoicing of /ɣ/ to /x/ after syncope followed by the common development of /xθ/ to /xt/; the vocalism represents a development /iu̯/ → /ia̯~ja/ (→ /a/). For the West Midland forms þrituðe, þrituðe, see twentithe.

• IPA^(key): /ˈθritiːð(ə)/, /ˈθritið(ə)/, /-θ(ə)/
• IPA^(key): /ˈθriˌtøːð(ə)/, /ˈθrityð(ə)/ (Southwest Midland)
• IPA^(key): /ˈθriˌtaxt(ə)/ (Kent)

thrittithe

1. thirtieth

• English: thirtieth (obsolete thirteth, thirtith)
• Middle Scots: threttieth
  • Scots: thrittiet

thrittithe

1. Something in the thirtieth position.

• English: thirtieth (obsolete thirteth, thirtith)
• Middle Scots: threttieth
  • Scots: thrittiet

• “thrī̆tīthe, num.”, in MED Online, Ann Arbor, Mich.: University of Michigan, 2007.
• “threttieth, thret(t)yd, thirtieth, adj. and num.”, in The Dictionary of the Scots Language, Edinburgh: Scottish Language Dictionaries, 2004–present, →OCLC, reproduced from William A[lexander] Craigie, A[dam] J[ack] Aitken [et al.], editors, A Dictionary of the Older Scottish Tongue: […], Oxford, Oxfordshire: Oxford University Press, 1931–2002, →OCLC.
• Ross, Alan S. C.; Berns, Jan (1992), “Germanic”, in Jadranka Gvozdanović, editor, Indo-European Numerals, Mouton de Gruyter, →DOI, →ISBN, →OCLC, page 686