Jettison sits next to 4 phonetic neighbors — Jett, Jackson, and Garrison are the closest matches by sound. Most share Jettison's Old French via Latin-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"to throw overboard, to cast away"
"initials: various combinations (Andrew Charles, Anthony Cole, etc.)"
"round, short person"
"what is given, what is cast"
"hawk-like; stately"
"divinely favored"
"tax collector, rent farmer"
"The lord is high"
"dearly loved"
"undulating; like a wave"
"weapon, mace bearer"
Similar sound: These names share phonetic patterns with Jettison — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old French via Latin origins, giving them the same cultural heritage as Jettison.
Rhythm: Jettison is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.