词根词缀：hebdoma-

【来源及含义】Greek: seventh

【同源单词】hebdomad, hebdomadal, hebdomadary

词根词缀：hepta-, hept-

【来源及含义】Greek: seven; normally used as a prefix

【同源单词】hebdomad, hebdomadal, hebdomadally, heptachord, heptachromic adjective, heptad