iphant (long-lived, litearally ”year-full”), pl. iphaint. The spelling used in the source is ”ifant” (LR:400 s.v. YEN), but since the f arises from earlier (n > m +) p via nasal mutation, it should be written ph according to the spelling conventions described in LotR Appendix E.
Noldorin
ifant
adjective. aged, having lived long, (lit.) year-full
ifant
adjective. aged, having lived long, old (with no connotation of weakness)
Author of Dorgannas Iaur (WJ/192). His first name seems to be a combination of [N.] taur “mighty” and hîr “lord”, while his second name is simply ifant “aged” (as suggested by David Salo, GS/358).