Answer: dodeca

AnswerCrossword Clue
DODECATwelve (prefix)
DODECA3 : tri- :: 12: ...
DODECATwice hexa-
DODECAPrefix for twelve
DODECATwelve: Prefix.
DODECATwelve: Prefix
DODECAComb. form for 12
DODECAPrefix with hedron