While
one may apply the term tool loosely to many things that are means to an end
(e.g., a fork), strictly speaking an object is a tool only if, besides being
constructed to be held, it is also made of a material that allows its user to
apply to it various degrees of force. If repeated use wears part of the tool
down (like a knife blade), it may be possible to restore it; if it wears the
tool out or breaks it, the tool must be replaced. Thus tool falls under the
taxonomic category implement, and is on the same taxonomic rank as instrument,
utensil, device, or ware.