What Irish boys' names begin with U?

Ualtar (“OOL-tar”), Ultán (“UL-tawn”).

Irish Names Starting With U — Meanings & Pronunciations

A B C D E F G H I J K L M N O P R S T U W

Ualtar “OOL-tar” Boy's name the Irish form of Walter Ultán “UL-tawn” Boy's name 'an Ulsterman' — from Ulaid Úna “OO-na” Girl's name possibly from uan, 'lamb', or úan, 'hunger'; disputed

Ualtar · “OOL-tar” · Boy's name · also Walter, Ualtair
The Irish form of Walter. The root of the surname Mac Uaitéir, Watters, carried in by Norman and later settlers and gaelicised in the usual way.
Ultán · “UL-tawn” · Boy's name · also Ultan
'an Ulsterman' — from Ulaid. St Ultán of Ardbraccan is remembered for taking in the children orphaned by the Yellow Plague of the 660s and feeding them himself — one of the earliest accounts of institutional care for children in Europe.
Úna · “OO-na” · Girl's name · also Oona, Oonagh, Una, Winifred
Possibly from uan, 'lamb', or úan, 'hunger'; disputed. A favourite of the Gaelic aristocracy, several Únas appear among the O'Briens and O'Neills, and, in folklore, the name of the queen of the fairies alongside Finvarra. Sometimes anglicised, for no good reason, as Winifred or Agnes.

Listed on the atlas under another spelling, but the U form is the one many families carry — they are the same name.

Uilliam “LEE-am” listed as Liam

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