HEPTAD
Meaning of HEPTAD in English
transcription, транскрипция: [ ˈhep-ˌtad ]
noun
Etymology: Greek heptad-, heptas, from hepta
Date: 1660
: a group of seven
Merriam-Webster's Collegiate English vocabulary.
Энциклопедический словарь английского языка Merriam Webster.
2003