insë "himself" and "herself", 3rd person sg. personal reflexive pronoun, apparently covering both genders, e.g. *tiris insë "(s)he watches him/herself" (but apparently the general reflexive pronoun immo may also be used, and it may even be preferable since the cluster ns seems unusual for Quenya). Compare insa, the corresponding impersonal form. Insë is derived from earlier imsë, a form that was possibly also used in Quenya (unless "imse" in Tolkien's manuscript is intended as an etymological form only, though it is not asterisked) (VT47:37)
Quenya
insa
itself
insa
pronoun. itself
Elements
Word Gloss im- “same” sa “it (inanimate); that”
insë
himself
sa
it
sa pron. "it", 3rd person sg, corresponding to the ending -s (VT49:30). Used of inanimate things or abstracts (VT49:37; plants are considered animate; see se). For sa as object, cf. the sentence ecë nin carë sa "I can do it" (VT49:34). Stressed sá (VT49:51). Ósa "with it" (VT43:36). Also compare the reflexive pronoun insa "itself", q.v. In one text, sa is also defined as "that" (VT49:18); apparently Tolkien also at one point considered giving sa a plural significance, so that it meant *"they, them" of inanimate things, the counterpart of "personal" té (VT49:51).
sa
pronoun. it
imma
itself
imma *"itself", impersonal reflexive pronoun referring to the "same thing" (VT47:37) as the subject; compare immo.
insa *"itself", 3rd person sg. impersonal reflexive pronoun, e.g. *tiris insa "it watches itself" (but apparently the general reflexive pronoun immo may also be used, and it may even be preferable since the cluster ns seems unusual for Quenya). Compare insë, the corresponding personal form.