1: Aodhán de Tegid -New Name (NP)
Submitter desires a masculine name.
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Aodhán - is a masculine Irish Gaelic given name found in Cornish (and other) Personal Names from the 10th century
https://www.s-gabriel.org/names/tangwystyl/bodmin/given2.htm#Given2 sn. Aedan, which says that "Although versions of this name are not uncommon in Old English and Medieval Welsh records, it is most likely Irish Aodhán rather than a Brythonic cognate.
On Concerning the Names Aidan,Aédán, Aodh, and the Like found at https://medievalscotland.org/problem/names/aidan.shtml at the top of the page "Aidan is a modern English spelling of the early medieval Gaelic name Áedán. It was relatively common in early medieval Ireland, and was the name of at least two 6th and 7th century saints. In the late Middle Ages, the saint's name was spelled Aodhán, but the name appears to have dropped out of common use after the 10th century or so. Its modern popularity dates to a revival in the 19th or 20th century. (Withycombe; OCM; Woulfe; CE; Annals)"
Index of Names in Irish Annals: Áedán (https://medievalscotland.org/problem/names/aidan.shtml) Look in the raw data on the page to find instances of "Aodhan"
de Tegid - A Simple Guide to Constructing 13th Century Welsh Names (https://heraldry.sca.org/names/welsh13.html)
Bynames Based On Location. The typical nickname based on location simply uses the proper name of a place after the given name. In this document, Latin de is sometimes placed before the place-name.
On https://en.wikipedia.org/wiki/Bala_Lake the first sentence is "Bala Lake (Welsh: Llyn Tegid [ˈɬɨ̞n ˈtɛɡɨd])". We wouild drop the Llyn (lake) and maintain the Tegid as a byname following the pattern devised in the SCA documents listed above.