endë noun "core, centre, middle" (NÉD, EN, VT48:25)
Quenya
endë
noun. centre, middle, centre, middle; [ᴹQ.] core
endë
core, centre, middle
enda
heart
enda noun "heart", but not referring to the physical organ; it literally means "centre" (cf. endë) and refers to the fëa (soul) or sáma (mind) itself. (VT39:32)
entë
center
entë (2) noun "center" (VT41:16; endë is perhaps to be preferred, see entya)
entë
noun. centre
entya
central, middle
entya, enetya adj. "central, middle" (VT41:16; these forms, as well as the noun entë "centre", come from a late, somewhat confused source; the adjective #endëa and the noun endë from earlier material may fit the general system better, and #endëa is even found in the LotR itself as part of the word atendëa, q.v.)
tólë
centre
tólë noun "centre" (LT1:269; the word endë is to be preferred in Tolkien's later Quenya)
elwen
heart
elwen noun "heart" (LT1:255; rather hón or enda in LotR-style Quenya)
enquë
cardinal. six
enquë ("q") cardinal "six" (ÉNEK, VT48:4, 6, 9, VT49:57); enquëa ordinal "sixth" (VT42:25); see also enquië. According to VT48:8, the word for "six" may have been encë ("k") in very early Quenya (the form is asterisked by Tolkien), but this was altered to enquë under the influence of yunquë "twelve" (perceived as meaning "2 times 6", *yú-enquë, with the prefix yú- "twi-").
enquë
cardinal. six
hón
heart
hón noun "heart" (physical) (KHŌ-N); hon-maren "heart of the house", a fire (LR:63, 73; this is "Qenya" with genitive in -en, not -o as in LotR-style Quenya read *hon-maro?)
indo
heart, mood
indo (1) noun "heart, mood" (ID), "state" (perhaps especially state of mind, given the other glosses) (VT39:23), "mind, region/range of thought, mood" (PE17:155, 179), "inner thought, in fea as exhibited in character or [?personality]" (PE17:189). In another post-LotR source, indo is translated "resolve" or "will", the state of mind leading directly to action (VT41:13). Indo is thus "the mind in its purposing faculty, the will" (VT41:17). Indo-ninya,a word occurring in Fíriels Song, translated "my heart" (see ninya). In the compound indemma "mind-picture", the first element would seem to be indo.
órë
heart
órë (1) noun "heart" (inner mind), also name of tengwa #21 (Appendix E), "premonition" (VT41:13), "nearest equivalent of 'heart' in our application to feelings, or emotions (courage, fear, hope, pity, etc.)" (VT41:13). The órë apparently defines a person's personality, cf. the description of Galadriel in PM:337, that "there dwelt in her the noble and generous spirit (órë) of the Vanyar". Órenya "my heart" (VT41:11).
The word ᴹQ. ende first appeared in The Etymologies of the 1930s, glossed either “middle, centre” (Ety/ÉNED) or “core, centre” (Ety/NÉD), and derived from the root ᴹ√ENED “middle” (Ety/ÉNED). In notes from late 1960s Tolkien had {ened >>} ente “centre”, which he clarified was “not used of emotions or thought only physical” (VT41/12). In this context it was derived from √HENET “middle” (VT41/16). But in other writings from the late 1960s, the word as again ende from √ENED “middle” (VT48/25), and I believe √HENET > ente was a transient idea.
Neo-Quenya: Base on its 1930s glosses and the meaning of 1960s ente, I believe ende is a noun referring to a physical centre.