The usual Quenya form of the name S. Thingol (S/53). This name is a combination of sinda (or sindë) “grey” and collo “cloak” (SA/thind(d)). It also appeared in the longer forms Sindicollo and Sindacollo.
Conceptual Development: The first Qenya name for this character in the earliest Lost Tales was ᴱQ. Linwe Tinto, but this was soon revised to ᴱQ. Tinwe Linto, the form most frequently used at this early stage (LT1/106, 130). Later in the Lost Tales Tolkien briefly used ᴱQ. Tinto Ellu, then reverted back to Tinwe Linto before introducing the name ᴱQ. Singoldo (LT2/50-1). The last of these names is quite close to the final form of his Quenya name. Note that Sol. Ellu appeared elsewhere as a Solosimpi name (LT1/155), and was the precursor to Q. Elwë. The meaning of these early Qenya names is unclear, though in an early Noldorin word list, its cognate ᴱN. Thingol is said to derive from ᴱN. thing “prince” (PE13/154).
In Silmarillion drafts and notes from the early 1930s, Tolkien used ᴹQ. Sindingul >> ᴹQ. Tindingol for his Quenya name (SM/264, 270; LR/112). In the mid-30s, he changed it to ᴹQ. Sindo “the Grey” (LR/119, 215), which is the form appearing in The Etymologies (Ety/THIN). The final form Q. Singollo emerged in Silmarillion revisions from the 1950s-60s (MR/82).
Singollo (þ) contraction of Sindicollo, q.v. (Silm)