Derek sits next to 3 phonetic neighbors — Derrick, Eric, and Darrick are the closest matches by sound. Most share Derek's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"ruler of the people"
"broad valley, broad hillside"
"one who hunts"
"exalted, noble, high"
"great, magnificent"
"God has heard, thankful to God"
"son of Benedict/Benjamin"
"round, barrel-maker"
"wave, abundant, learned"
"son of Carr (marsh dweller)"
"warrior's town"
"God is gracious"
"greatest, largest"
"divine gift"
"Beauty, grace"
"fortunate, good"
"strength, manly beauty"
"from the brook"
"crooked river, winding stream"
"Yahweh is merciful"
"little fire"
Similar sound: These names share phonetic patterns with Derek — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Germanic origins, giving them the same cultural heritage as Derek.
Rhythm: Derek is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.