ᴹ√SMAG “soil, stain”
A root in The Etymologies of the 1930s glossed “soil, stain” with derivatives {mael >>} N. hmael “stain; stained” and {maw >>} N. hmaw “soil, stain” (Ety/SMAG; EtyAC/SMAG). Tolkien first gave this root as ᴹ√MAG⁽²⁾ (EtyAC/MAG²).
√SNAG “wound, gash”
A root appearing in the Outline of Phonology (OP2) from the early 1950s, first as √(S)NAG “wound” (PE19/92 note #110) and then as √SNAG “wound, gash” in red-ink revisions made in 1959, ultimately having derivatives like Q. nahte/S. naedh “wounding, wound” (P19/91). It might be a later iteration of ᴱ√SṆKṆ “rend, tear” from Qenya Lexicon of the 1910s with derivative ᴱQ. sanka “rend, jab” (QL/85). This early root was apparently confused with ᴱ√ÞṆKṆ “*hate”; see that entry for discussion.
ᴱ√SṆTṆ “esteem”
The root ᴱ√SṆTṆ “esteem” appeared in the Qenya Lexicon of the 1910s with derivatives ᴱQ. santa “dear, beloved” and ᴱQ. sinte “esteem; estimate, computation” (QL/85). There are no signs of this root in Tolkien’s later writing, but I think it is worth positing a Neo-Root ᴺ√SINIT for “esteem” and “estimate” words.
ᴱ√SŌ
A root in the Qenya Lexicon of the 1910s that Tolkien said was used only for the prefix ᴱQ. so- “grouped, together”, but immediately under it he wrote another (non-prefixal?) root ᴱ√SŌ with a single derivative ᴱQ. sóma “state, condition” (QL/85). There are no signs of either of these functions for this root in Tolkien’s later writing.
ᴹ√SOL “*surf”
An unglossed root in The Etymologies of the 1930s with derivatives like ᴹQ. solor “surf” (< ᴹ✶solos) and ᴹQ. Solonyeldi “*Surf Singers” as another name for the Teleri (Ety/SOL). It is a later iteration of ᴱ√SOLO from the Qenya Lexicon of the 1910s with derivatives like ᴱQ. solme “wave” and ᴱQ. solor “surf”, and was in this period the basis for the name ᴱQ. Solosimpe “Shore Piper” (QL/85). Words in the contemporaneous Gnomish Lexicon like G. thloss “breaker” and G. Thlossibrim = ᴱQ. Solosimpi were derived from primitive thol-, indicating the early form of the root was actually ᴱ√ÞOLO (GL/73), which in Gnomish was intermingled with derivatives of ᴱ√FALA “*wave” (GL/33, 35).
The etymology of the 1930s ᴹQ. solor “surf” < ᴹ✶solos is problematic, in that it shows final -s > -r, a remnant of ideas from Early Qenya. Tolkien’s use of Q. Falmari “Wave-folk” in later writings as the primary alternate name for the Teleri (S/53; PM/386) calls into question the continued validity of ᴹ√SOL. Nevertheless, I think it is useful to retain this root in Neo-Eldarin to salvage some early words like ᴱQ. sóla “tide”.
ᴱ√SOVO “wash”
A root in the Qenya Lexicon of the 1910s with variants ᴱ√SOVO and ᴱ√SOW̯O glossed “wash”, having derivatives like ᴱQ. sovo- “wash” and ᴱQ. saune “bath” (QL/85), the latter a result of the Early Qenya sound change whereby [ei], [ou] became [ai], [au] (in later Quenya phonology, these generally became [ī], [ū]). In the contemporaneous Gnomish Lexicon, the primitive form was given as soƀ with derivatives like G. sô- “wash, clean, bathe” and G. sôn “pure, clean” from primitive ᴱ✶sou̯na (GL/68). This last primitive form reappeared in Early Noldorin Word-lists from the 1920s where it had derivatives like ᴱQ. sauna “clean” and ᴱN. hûn “polished, burnished, shining” (PE13/148).
Neo-Eldarin: I think it is worth positing an Neo-Root ᴺ√SOW “wash” and variant ᴺ√SAW “bath” to salvage some of these early words.