Christopher Tolkien gave this root as carak- in the Silmarillion appendices as the basis for Q. carca/S. carch “fang” along with various related words (SA/carak). Its origin dates all the way back to the earliest version of the language: its first iteration was (unglossed) ᴱ√KṚKṚ in the Qenya Lexicon of the 1910s, already the basis for ᴱQ. karka/G. carc “fang” (QL/48; GL/25), though its other derivatives were more variable in form due to the vagaries of the phonetic developments of syllabic ṛ in Early Qenya and Gnomish. After Tolkien dropped syllabic consonants from the vowel system of Primitive Elvish, the root became ᴹ√KARAK “sharp fang, spike, tooth” in The Etymologies of the 1930s (Ety/KARAK). The frequent appearance of its derivatives in later writings indicate its continued validity.
Primitive elvish
kar
root. do, make, build, do, make, build, [ᴹ√] construct
karani-stīrē
masculine name. Karani-stīrē
karak
root. *sharp fang, spike, tooth, [ᴹ√] sharp fang, spike, tooth
karap
root. *talk, speech
The root √KARAP appeared with various forms and meanings throughout Tolkien’s life. Perhaps the earliest iteration was ᴱ√KᴬRPᴬR [KṚPṚ] “pluck” from the Qenya Lexicon of the 1910s (QL/45), with derivatives in the contemporaneous Gnomish Lexicon as well such as G. carp “bundle, bunch” and G. crib- “gather, pluck” (GL/25, 27). The verb form ᴱ✶kṛp- > ᴱQ. karpe “pluck” reappeared in the Early Qenya grammar of the 1920s (PE14/58).
The root ᴹ√KARPA appeared unglossed in the first version of Tengwesta Qenderinwa (TQ1) from the 1930s as an example of a KALTA-stem root, but whether it was related to earlier √KṚPṚ is unclear. Possibly also related is N. carab “hat”, appearing in N. Amon Carab which was an earlier name of S. Amon Rûdh.
Finally, the root √KARAP appeared in notes probably dating to the early 1960s, serving as the basis for various “speech” words such as Q. carpa-/S. carfa- “talk, speak, use tongue”, but that root was probably replaced by √PAKAT (PE17/126). Given the muddled history of this root, I would mostly avoid its use for purposes of Neo-Eldarin, though it is needed to justify N. carab “hat”.
kar-
verb. do, make
karani
adjective. red
kariyendi
noun. a process of manufacture
karandi
noun. making
kas
root. head
The root for “head” was established very early in Tolkien’s Elvish languages, appearing in the Qenya Lexicon of the 1910s as ᴱ√KASA “head” (QL/45), though in this period its Qenya derivative was ᴱQ. kar (kas-) because [[eq|final [s] became [r]]] in Early Quenya (PE12/26). It had derivatives in the contemporaneous Gnomish Lexicon such as G. cas “head, skull” (GL/25), a word that reappeared in Early Noldorin word lists of the 1920s as ᴱN. cas “skull” (PE13/140).
The root ᴹ√KAS “head” reappeared in The Etymologies of the 1930s, still with the form ᴹQ. kár (kas-) “head” (Ety/KAS), but Tolkien eventually abandoned the Early Qenya phonology and the Quenya form became Q. kas after some vacillation (PE19/103). The root √KAS “head” continued to appear frequently in Tolkien’s later writing (PE17/114; PE21/70; VT42/12).
pakat
root. *talk, speech
This root appeared in notes probably dating to the early 1960s as the basis for words for “speech”, probably replacing another root √KARAP of similar meaning, and with a deleted variant √PATAK (PE17/126). The root √PAKAT itself was probably a restoration of a (hypothetical) early root ✱ᴱ√PAKATA, the likely basis for “speech” words in the Gnomish Lexicon of the 1910s such as G. pactha- “utter, speak, talk” and G. paithron “orator” (GL/63).
kārimā
adjective. able to be done, feasible
kasraya
noun. a tressure
kas
noun. head
kat
root. shape, shape, [ᴹ√] make
The root ᴹ√KAT “shape” first appeared in The Etymologies of the 1930s with derivatives ᴹQ. kanta- “to shape”, ᴹQ. kanta “shaped”, and N. echad- “fashion, shape” (Ety/KAT). All these derivatives reappeared in Tolkien’s later writings, though Q. canta was more typically used as the noun “shape” (PE17/175; PE18/84, 90). The root appeared frequently in both the first and second version of Tengwesta Qenderinwa as an example of a biconsonantal root (TQ1: PE18/34, 46, 62; TQ2: PE18/84-85, 87, 89-90, 95).
kawāk
noun. crow
lemek
root. [unglossed]
An unglossed root in the Outline of Phonology from the early 1950s illustrating certain phonetic combinations (PE19/98), and therefore possibly not a “real” root.
nelek
root. tooth
phut
root. [unglossed]
An unglossed root appearing in the second version of Tengwesta Qenderinwa (TQ2) as an etymological variation of √PUT (PE18/90).
sal
root. [unglossed], *harp(ing), lyre
The unglossed root ᴱ√SALA appeared in the Qenya Lexicon of the 1910s with derivatives like ᴱQ. salma “lyre, small harp” and ᴱQ. salumbe “harping, music” (QL/81). The root √SAL appeared again Common Eldarin: Verb Structure from the early 1950s to illustrate the reformed perfect form of its verb Q. asálie (PE22/132), but since these later forms are unglossed it is unclear whether they have the same meaning (“✱harp(ing)”) as the earlier version of the root.
stuk
root. [unglossed]
tig
root. [unglossed]
A root appearing in Late Notes on Verb Structure (LVS) from 1969 as the basis for the verb Q. tinga- “go (for a long while)” (PE22/157). The etymology was marked with an “X” and so was probably a transient idea (PE22/157 note #70).
graw Reconstructed
root. [unglossed], [ᴹ√] dark, swart
This root appeared as a primitive form grawa serving as the basis of the word Q. roa “bear” >> “dog” in notes on monosyllabic roots from 1968 (VT47/35); a Sindarin derivative S. graw “bear” appeared in other notes written around the same time (VT47/12). Patrick Wynne suggested that in the sense “bear” grawa might be connected to the root ᴹ√GRAWA “dark, swart” from The Etymologies of the 1930s (EtyAC/GRAWA).
Tolkien introduced the root √KAR with the sense “do, make” very early, and it retained this form and meaning for his entire life. It appeared as ᴱ√KARA “do, make” in the Qenya Lexicon of the 1910s (QL/45), as ᴹ√KAR “make, build, construct” in The Etymologies of the 1930s (Ety/KAR), and in numerous other places in various notes, including a last known appearance in verbal notes from 1969 as √KAR “do” (PE22/155). Though its exact set of derivatives varied over time, the root itself was extremely stable in Tolkien’s mind.