1. pentimal - Noun
2. pentimal - Adjective
pentimal (not comparable)
(rare, of a positional numeral system) Using a base of 5; quinary.
(rare, uncountable) The abstract numeral system underlying any pentimal numeral system; quinary.
(rare, countable) A numeral as written in such a system; a quinary.
Source: en.wiktionary.org