Easternmost outpost of the land of Valinor (S/59). This name is a combination of tol “island” and eressëa “lonely”, though the island was sometimes simply called Eressëa. It may be that this island was sometimes still reachable by mortals after the world was bent and the lands of Aman were removed from the world.
Conceptual Development: This name dates back to the earliest Lost Tales, and the earlier names ᴱQ. Tol Eressea and ᴹQ. Tol Eressea have the same form and meaning (LT1A/Tol Eressëa; Ety/ERE, TOL²). Perhaps the most important function of this island in Tolkien’s tales was as the place where Elvish lore was transmitted to Men, first to ᴱQ. Eriol in the earliest stories and to Ælfwine in later tales. Although Christopher Tolkien removed this idea from the published version of The Silmarillion to prevent confusion, it persisted into J.R.R. Tolkien’s writings in the 1950-60s.
tol noun "island, isle" (rising with sheer sides from the sea or from the river, SA:tol, VT47:26). In early "Qenya", the word was defined as "island, any rise standing alone in water, plain of green, etc" (LT1:269). The stem is toll-; the Etymologies as published in LR gives the pl. "tolle" (TOL2), but this is a misreading for tolli (see VT46:19 and compare LT1:85). The primitive form of tol is variously cited as ¤tolla (VT47:26) and ¤tollo (TOL2).