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Definitions

tool

[tool] / tul /
NOUN
instrument used to shape, form, finish
Synonyms
STRONGEST
apparatus appliance device engine gadget gizmo machine means mechanism utensil weapon
STRONG
contraption contrivance implement whatchamacallit
Antonyms
STRONGEST
plaything
WEAK
toy
NOUN
person who can be manipulated by another
Synonyms
STRONG
accessory accomplice agent auxiliary chump creature dupe figurehead flunky go-between greenhorn hireling idiot intermediary jackal lackey mark messenger minion patsy pawn peon puppet stooge sucker
WEAK
easy mark stool pigeon

Usage

What are other ways to say tool? A tool is a contrivance held in and worked by the hand, for assisting the work of (especially) mechanics or skilled laborers: a carpenter's tools. An instrument is anything used in doing a certain type of work or producing a certain result, especially such as requires delicacy, accuracy, or precision: surgical or musical instruments. An implement is any tool or contrivance designed or used for a particular purpose: agricultural implements. A utensil is especially an article for domestic use: kitchen utensils. 

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.