Griffen sits next to 4 phonetic neighbors — Griffin, Griffith, and Grifton are the closest matches by sound. Most share Griffen's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"strong lord, fierce chief"
"one who delivers goods, agent"
"rainbow"
"fern plant (feathery frond)"
"from the open, beloved"
"lively energy, kicks"
"God is exalted, gift of God"
"wished for child"
"to heal, to cure"
"supplanter, one who takes another's place"
"God appears (Theo-phania)"
"modern coinage combining Matt + -ix suffix"
"son of Ben, son of the right hand"
"highland, high ground"
"olive tree"
"curly-haired"
"creative variant of Isaiah"
"little swift one, bright and pleasant"
"dweller by the red river crossing"
"thorn hedge enclosure"
"victory of the people"
Similar sound: These names share phonetic patterns with Griffen — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Welsh origins, giving them the same cultural heritage as Griffen.
Rhythm: Griffen is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.