-tḗr
From Proto-Indo-European *-tḗr, with nominative η made common to all cases with original syncopation or ε; compare its use in ἀστήρ (astḗr) (always with ε) and γαστήρ (gastḗr) (either with oblique ε throughout or original syncopation).
-τήρ • (-tḗr) m (genitive -τῆρος); third declension
- Added to verb stems to form masculine agent nouns
- δίδωμι (dídōmi, “(δω-, weak stem δο- to give”) + -τήρ (-tḗr) → δωτήρ, δοτήρ (dōtḗr, dotḗr, “a giver”)
- ἐργάζομαι (ergázomai, “to work”) + -τήρ (-tḗr) → ἐργαστήρ (ergastḗr, “workman”)
- καθίημι (kathíēmi, “to let down, descend”) + -τήρ (-tḗr) → καθετήρ (kathetḗr, “anything let down into”)
- κλύζω (klúzō, “to wash, cleanse”) + -τήρ (-tḗr) → κλυστήρ (klustḗr, “a clyster-pipe, syringe”)
- ἵστημι (hístēmi, “(weak stem στα- to stand”) + -τήρ (-tḗr) → στατήρ (statḗr, “a weight”)
- χαράσσω (kharássō, “(χαράκ-j- to engrave”) + -τήρ (-tḗr) → χαρακτήρ (kharaktḗr, “an engraver”)