compartmentalist

Etymology tree
Proto-Indo-European *ḱe?
Proto-Indo-European *ḱóm
Proto-Italic *kom
Proto-Italic *kom-
Latin com-
Proto-Indo-European *perh₃-der.?
Proto-Italic *partis
Latin pars
Latin partiō
Latin partior
Latin compartīrībor.
Italian compartire
Proto-Indo-European *-mn̥
Proto-Indo-European *-mn̥tom
Proto-Italic *-mentom
Latin -mentum
Italian -mento
Italian compartimentobor.
Middle French compartimentder.
English compartment
Proto-Indo-European *h₂el-der.?
Proto-Italic *-ālis
Latin -ālisbor.
Old French -albor.
▲
Latin -ālis
Old French -elbor.
▲
Latin -ālisbor.
Middle English -al
English -al
English compartmental
Proto-Indo-European *-id-
Proto-Indo-European *-yéti
Proto-Indo-European *-idyéti
Proto-Hellenic *-íďďō
Ancient Greek -ῐ́ζω (-ĭ́zō)
Proto-Hellenic *-tās
Ancient Greek -τής (-tḗs)
Ancient Greek -ῐστής (-ĭstḗs)bor.
Latin -istader.
Old French -istebor.
Middle English -ist
English -ist
English compartmentalist
From compartmental + -ist.