Similar to the English-language suffixes:
-able
-ible
e.g.: something admirable (that which is admired), something edible (that which can be eaten), etc.
Examples in Nahuatl:
chiyaloni, chiyeloni = that which is waited for or expected
pialoni = that which is guarded, kept
Example of a tool:
apozoniloni = a tool for mixing cacao or chocolate
ontentli in pialonj, in neiollotilonj, in concauhtiaque = two words worthy of being guarded, worthy of being remembered, which they left as they went (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 6 -- Rhetoric and Moral Philosophy, No. 14, Part 7, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 91.
Also, a great many nouns ending in -oni refer to a tool or a person associated with a certain action. An advanced search for dictionary entries ending in -oni will provide numerous examples. (SW)