The Elvish words for “blue” remained very similar throughout Tolkien’s life, but underwent a number of minor conceptual shifts. The word ᴱQ. lūne “blue, deep blue” appeared in the Qenya Lexicon of the 1910s in a collection of words along with ᴱQ. lūle “blue stone, sapphire”, but no root was given (QL/55). The word for “blue” in the contemporaneous Gnomish Lexicon was G. luim (GL/55). In The Etymologies of the 1930s, the root for “blue” was ᴹ√LUG with derivatives ᴹQ. lúne and N. lhûn (Ety/LUG²).
Meanwhile, the root ᴹ√LUY appeared in The Etymologies with derivatives ᴹQ. luina and Dor. luin “pale” (EtyAC/LUY), probably connected to ᴱN. Draugluin “Werewolf Pale” from the Lays of Beleriand of the 1920s (LB/205). But in The Etymologies the root ᴹ√LUY was rejected, and Dor. luin “pale” was reassigned to ᴹ√LUG² and then revised in form to Dor. lūn (Ety/LUG²; EtyAC/LUG²).
In addition, there was already evidence of a conceptual shift in the Noldorin words for blue in the 1930s, with the name N. Eredluin “Blue Mountains” being given as an alternative to N. Lhúnorodrim and N. Lhúndirien “Blue Towers” (Ety/LUG²), the latter appearing as N. Luindirien in contemporaneous Silmarillion narratives (LR/267). By the 1950s and 60s, the Sindarin and Quenya words for “blue” had firmly become S. luin (Let/448; S/54; UT/390) and Q. luinë (LotR/377; PE17/66, 71). The root √LUY “blue” appeared in notes from the late 1960s serving as the new basis for these “blue” words (VT48/23-24, 26).
All this made a mess for the river name S. Lhûn (LotR/1134) from The Lord of the Rings which was a remnant of Tolkien’s earlier ideas, and he struggled to find a new basis for that name as discussed by Patrick Wynne in his article on The Problem of Lhûn (VT48/26-29).
An orc from Isengard in the raiding party that capture Merry and Pippin.