from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Of fifth rank or order.
- adj. Consisting of five things; arranged in fives
- adj. To the base of five; represented by the numerals 0, 1, 2, 3 and 4.
from the GNU version of the Collaborative International Dictionary of English
- adj. Consisting of five; arranged by fives.
from The Century Dictionary and Cyclopedia
- Divided in a set of five, as parts or organs of most radiates.
- In zoology, same as quinarian.
- n. A whole composed of five parts or elements.
- Based upon five.
In its structure the quinary is the simplest, the most primitive, of the natural systems.
Examples of this are furnished in a more or less perfect manner by nearly all so-called quinary-vigesimal and quinary-decimal scales.
“Khumásiyah” which Lane (ii. 438) renders “of quinary stature.”
Here, says Pantagruel, doth he more amply and fully insinuate unto us, by the token which he showeth forth of the quinary number, that you shall be married.
In view of these facts, and of the extreme readiness with which a tribe would through its finger counting fall into the use of the quinary method, it does not at first seem improbable that the quinary was _the_ original system.
VI., etc., with equal certainty suggests quinary counting, but the Latin language contains no vestige of anything of the kind, and the whole range of Latin literature is silent on this point, though it contains numerous references to finger counting.
Any number system which passes the limit 10 is reasonably sure to have either a quinary, a decimal, or a vigesimal structure.
One remarkably interesting number system is that exhibited by the Mosquito tribe  of Central America, who possess an extensive quinary-vigesimal scale containing one binary and three senary compounds.
As the count proceeds further, the quinary base may be retained, or it may be supplanted by a decimal or a vigesimal base.
In the simplicity and regularity of its construction it is so noteworthy that it is worth repeating, as the first of the long list of quinary systems given in the following pages.