subchairman

Etymology tree
Proto-Indo-European *upó
Proto-Italic *supo
Latin sub
Latin sub-der.
English sub-
Proto-Indo-European *ḱe?
Proto-Indo-European *ḱóm
Proto-Indo-European *ḱm̥-th₂der.?
Proto-Hellenic *kətá
Ancient Greek κατά (katá)
Proto-Indo-European *sed-der.
Proto-Indo-European *sedreh₂
Proto-Hellenic *hédrā
Ancient Greek ἕδρα (hédra)
Ancient Greek κᾰθέδρᾱ (kăthédrā)bor.
Latin cathedrader.
Old French chaierebor.
Middle English chayere
English chair
Proto-Indo-European *mon-
Proto-Germanic *mann-
Proto-West Germanic *mann
Old English mann
Middle English man
Middle English -man
English -man
English chairman
English subchairman
From sub- + chairman.