Mckay sits next to 4 phonetic neighbors — MacKay, McCoy, and Mackay are the closest matches by sound. Most share Mckay's Scottish cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"son of Aodh (fire)"
"the Lord is salvation"
"variant of Jason"
"son of Hendrik"
"gift of God's grace"
"modern invented name combining Zay and lyn"
"slender, narrow"
"supplanter, one who follows at the heel"
"from Sebastos (venerable city)"
"Ireland, land of the west"
"man, husband"
"golden, made of gold"
"command, edict, beautiful example"
"destroyer of enemies, world peace"
"to shine, emit light"
"from the rippling water"
"God is gracious"
"name of God"
Similar sound: These names share phonetic patterns with Mckay — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Scottish Gaelic origins, giving them the same cultural heritage as Mckay.
Rhythm: Mckay is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.