The Quenya name of S. Aredhel (PM/345). Its second element is the feminine suffix -issë (PM/345) and its initial element seems to be írë “desire”, so perhaps the name means “✱Desirable Lady”. See S. Íreth and Aredhel for further discussion.
Quenya
írissë
desire
írissë
feminine name. *Desirable Lady
-issë
-issë
-issë a feminine ending, as in Írissë (PM:345)
írë
noun. desire, desire, [ᴹQ.] longing
írë
desire
írë (1) noun "desire". (ID). In the pre-classical Tengwar system presupposed in the Etymologies, írë was also the name of a long carrier with an i-tehta above it, denoting long í. (VT45:17).
milmë
desire, greed
milmë noun "desire, greed" (MIL-IK)
yesta-
desire
yesta- (1) vb. "desire" (YES, VT46:23; the latter source indicates that Tolkien did write yesta- with a final hyphen, indicating that this is "desire" as a verbal stem, not as a noun).
Írissë fem. name (PM:345), evidently connected to írë "desire".