ᴱ√BOTO root. “*back, behind, after”
The root ᴱ√POT-I appeared (unglossed) in the Qenya Lexicon of the 1910s with various derivatives having to do with the “back” or “rear” (QL/75). Many of its Gnomish equivalents began with b-, which would typically indicate the true form of the root was ᴱ√BOT-I, given that initial b- > p- in Early Qenya. In this case, though, Tolkien specifically said that the Gnomish forms like G. bont “back(wards)” were the result of “atonic development” via the loss of an initial vowel (GL/23), and there were in fact Gnomish forms beginning with p- such as G. pont “the back, reverse or far side” (GL/64).
In the Early Noldorin of the 1920s, however, Tolkien gave the root as *bot- (PE13/139), possibly indicating a conceptual shift despite the continued presence of Qenya derivatives beginning with p-. This root was likely the conceptual precursor to various later directional roots like √OPO or √APA.
References ✧ PE13/139; QL/75