pentimal means using a base of 5; quinary. Lexicurio rates it Sui generis — a strength score of 87 out of 100.
Etymology
From pent-, by analogy with decimal.
adj
- Using a base of 5; quinary.
noun
- The abstract numeral system underlying any pentimal numeral system; quinary.
- A numeral as written in such a system; a quinary.