The usual Quenya word for “maiden” derived from the root √WEN(ED) (Ety/WEN; PE17/191; VT47/17). Tolkien usually wrote this word as wende but it would be pronounced and written vende in modern Quenya.
Conceptual Development: This word was fairly stable in Tolkien’s mind. In the Qenya Lexicon of the 1910s this word was ᴱQ. ’wen (wend-) “maid, girl” with longer variant wendi “maiden” derived from the early root {ᴱ√WENE >>} ᴱ√GWENE (QL/103). The form wendi was also mentioned in the contemporaneous Gnomish Lexicon, but there the root was {ᴱ√gw̯ene >>} ᴱ√gu̯eđe (GL/45). In the Nieninqe poem written around 1930 it was ᴱQ. wende “maiden” (MC/215), a form that reappeared in the version of the poem from the 1950s as well (PE16/96).
In The Etymologies of the 1930s Tolkien gave this word as ᴹQ. wende, vende “maiden” under the root ᴹ√WEN-ED of the same meaning (Ety/WEN), In a marginal note Tolkien said that derivatives of ᴹ√WEN-ED should be transferred to ᴹ√GWEN, and under that root Tolkien indicated there was blending with ᴹQ. wende “maid” (Ety/GWEN).
In later writings Tolkien mostly used the form wende, but in Quenya prayers from the 1950s he once wrote Vénde, where the long é was probably a slip (VT44/5, 10). Likewise in later writings Tolkien mostly gave the root as √WEN(ED), but in one place considered deriving wende from √GWEN “fair” (PE17/191). Finally he generally translated this word as “maiden”, but in Quenya Prayers from the 1950s used it with the sense “virgin” in reference to the Virgin Mary (VT44/5, 12).
Neo-Quenya: It is tricky to reconcile Tolkien’s regular use of the form wende with the root √WEN(ED), since ancient w became v in Quenya, making the expected form vende. To retain wende, the most straightforward explanation is that it was derived from strengthened ✱gwendē, since this initial cluster survived as w at least into Classical Quenya and possibly beyond. However, the strengthening of ✶wendē > ✱gwendē must have occurred after the Common Eldarin period, otherwise the Sindarin form would have been ✱✱bend, whereas Tolkien consistently used S. gwen(d).
Many Neo-Quenya writers avoid this question simply by revising the form to vende, a practice I recommend as well, though its suffixal form would (mostly) remain -wen. I also prefer to use vende mainly for “maiden, ✱young woman” and for “virgin” (of any gender) I recommend vénë.
A word given by Tolkien as Véne “Virgin” in the Quenya Prayer Ortírielyanna, a translation of Sub Tuum Praesidium (VT44/5-6). Tolkien initially wrote several hesitant forms Ven > Wen > We before writing Véne. In the last phrase he wrote down for the prayer, he revised it to Vénde though the prior phrase with Véne’ was not deleted. As suggested by Wynne, Smith, and Hostetter, Vénde was an alteration from Véne, and its long vowel was probably not intended (VT44/10). Elsewhere Tolkien used wendë for “virgin”, for example in the Quenya translation of the Litany of Loreto prayer (VT44/12); see the entry on vendë for further discussion.
Conceptual Development: In The Etymologies of the 1930s ᴹQ. wéne, véne was given as a word for “girl” or “maiden”, or possibly “virginity” (Ety/WEN).
Neo-Quenya: For purposes of Neo-Quenya, I think it is useful to be able to distinguish “virgin” and “maiden”. I’d use vénë for “virgin” and [ᴹQ.] venessë for “virginity” (irrespective of gender), but vendë for “maiden, ✱young woman” and vendelë for “maidenhood”.