English
infraclass
From infra- + class.
Proto-Indo-European *bʰer- ‘to bear, carry’
…
Proto-Italic *ferō ‘to carry, bear’
Latin ferō ‘to bear’
Latin īnferō ‘to carry, bring, put, place, or throw in,…’
Latin īnfrā ‘below’
English infra-
Proto-Indo-European *kelh₁- ‘to call’
Latin classis ‘a class or division of the people’
Middle French classe
English class
Today it means
noun A zoological classification sometimes inserted below subclass and above subterclass (rarely used) and superorder.
Language periods are conventional ranges, not dates for this word.
Etymograph / infraclass