√TAY root. “mark, line, limit; stretch, [ᴹ√] extend, make long(er)”
The root ᴹ√TAY first appeared in The Etymologies of the 1930s with the gloss “extend, make long(er)” and derivatives like ᴹQ. taile “lengthening, extension”, ᴹQ. taina “lengthened, extended” and N. taen “long (and thin)” (Ety/TAY). Tolkien considered making it a variant of ᴹ√TAƷ (EtyAC/TAY), perhaps intending ᴹ√TAY to refer to horizontal length as opposed to vertical ᴹ√TAƷ. The root ᴹ√TAY “stretch” also appeared in the first version of Tengwesta Qenderinwa (TQ1) from the 1930s as the basis for ᴹ✶tainā “long”, and there were various related linguistic terms like Q. ómataima “vocalic extension” and Q. ómatailë “vowel lengthening” that appeared in both the first and second version of Tengwesta Qenderinwa (TQ1: PE18/34, 45; TQ2: PE18/86, 95).
The root √TAJA “stretch” appeared in notes associated with the Quendi and Eldar essay of 1959-60 (VT39/7), and √TAY “stretch” appeared in a list of sound roots from around this same time (PE17/138). However, in notes on the origin of the river name S. Taeglin “*Boundary Singer”, Tolkien glossed √taya “mark, line, limit” with extension tayak as the basis for ✶taika “boundary, limit, boundary line” > S. taeg (WJ/309). Perhaps it was Tolkien’s intent that the sense “mark, line, limit” only applied to the extended form tayak.
References ✧ PE17/138, 187; VT39/7, 9; WJ/309
ᴹ√TAY root. “extend, make long(er), stretch”
References ✧ Ety/TAY; EtyAC/LIN¹, TAY; PE18/57