Loans do not undergo umlauting consistently; hence Uyghur has hell 'a moment ago, in a moment' (UTIL 5: 581) from Arabic hali 'present' with umlaut but hall 'its state' (Uyg hal 'state' from Arabic hal) without (UTIL 5: 454-457).
(17) Hence, Uzbek has /a/ in ayiz 'mouth' (OTIL 1: 561-562) (T ayiz, Uyg eyiz) as well as in yariq 'gap' (OTIL 1: 262) (T yaruq, Uyg yeriq) and yaruy 'light' (OTIL 1: 262) (T yaruq, Uyg yaruq).
The Old Turkic word yugun 'bridle' (Clauson 1972: 913) has undergone vowel lowering everywhere, too: (19) Uyg yugen (UTIL 6: 678), Uzb yugan (OTIL 2: 462), Kaz zugen (Bektaev 2001: 211), Krg jugon (Judaxin 1965: 272), Alt uygen (Baskakov and Toscakova 1947: 171), Xak cugen (Baskakov and Inkizekova-Grekul 1953: 324), Tuv cugen (Tenisev 1968: 549).
Uyg beket 'station, stop' (UTIL 1: 533), Uzb bekat 'station, stop, postal station' (OTIL 1: 97), Krg beket 'postal station' (Judaxin 1965: 126) and Kaz beket 'station, postal station' (Bektaev 2001: 99) probably developed from Old Turkic bekut, which Clauson (1972: 325) registers as a hapax legomenon derived from the verb stem beku-'to be firm'.
Old Turkic yoyun 'thick' (Clauson 1972: 904) maintains its high vowel only in Oghuz (Tur yogun, Tkm yoyi:n, TDS 297), while lowering has taken place elsewhere: Uyg yoyan 'huge, massive' (UTIL 6: 595), Uzb yoyan (OTIL 2: 356), Ili Salar yoyan (Yakup 2002: 130), Kaz zuwan (Bektaev 2001: 207).
in Uyg tot 'four' < T tort), and the initial /s/ has been assimilated to /c/ as in Uyg cac 'hair' < T sac.
For the dialect of Khotan (Uyg Xoten), forms like konel for Standard Uyghur konul 'heart', bugen instead of SUyg bugun 'today', toxa instead of toxu 'chicken' and oval in place of oyul 'son' are reported (Sayim 2007: 11).
Tur koru 'grove'), which is a nominal derivation from the verb qori= 'to protect' (Uzb qori-, Uyg qoru-), but this word survives regularly as Uyg qoruq (UTIL 4: 243, entry qoruq II) and Uzb qoriq (OTIL 2: 640) with meanings like 'field; shelter, cover, et cetera'.