Galaxy sits next to 4 phonetic neighbors — Galaxy, Allegra, and Kalani are the closest matches by sound. Most share Galaxy's Greek-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"the Milky Way, vast star system"
"my beautiful one"
"keeper of the keys"
"my strength"
"the color blue"
"of or pertaining to birth"
"land of the Britons"
"divine, pure"
"bright, shining one"
"table, flat-topped plateau"
"exalted, sublime"
"full of joy, brightness"
"lives near reed beds"
"God is my sun/lord"
"fair, bright (fionn) + warrior/hero (lagh)"
"strength of God"
"supplanter, one who follows at the heel"
"gift of God"
"new, new star"
"Quinn's meadow, meadow of the chief"
Similar sound: These names share phonetic patterns with Galaxy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Galaxy.
Rhythm: Galaxy is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.