Middle Primitive Elvish
lindā
adjective. sweet sounding
lin²
root. sing
lir¹
root. sing, trill
glir
root. sing, trill
* lindō
noun. singer
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
In The Etymologies, Tolkien considered a Noldorin variant of this root: ᴹ√GLIN with derivatives ᴹQ. lin-, N. glin- “to sing” and N. glinn “song, poem, lay”. He rejected this variant, however, and its derivatives became ᴹQ. lir-, N. glir- and N. glaer or glîr, all from the root ᴹ√(G)LIR.
After this changes, all of the remaining derivatives of ᴹ√LIN² were actually derived from primitive ᴹ✶lind-; this seems to be the case with derivatives of this root in later writings as well.