Deegan sits next to 4 phonetic neighbors — Keegan, Reagan, and Teagan are the closest matches by sound. Most share Deegan's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"descendant of the black-haired one"
"descendant of Grey"
"descendant of Cinneide"
"coastal land, border land"
"noble and ready"
"leader, sovereign"
"modern spelling of Coe (jackdaw bird)"
"God is salvation"
"raven, crow"
"born on Tuesday (Akan day name)"
"lake dweller, from the lake"
"ruler of supernatural beings"
"gracious defender"
"victory of the people"
"the fifth"
"from Airelle (Norman place name)"
"place of lime trees"
"God is gracious"
"order, universe"
"fox"
Similar sound: These names share phonetic patterns with Deegan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Irish Gaelic origins, giving them the same cultural heritage as Deegan.
Rhythm: Deegan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.