gadget

n. mechanical device; device useful for a particular job; contraption, contrivance; appliance, accessory

GADGET is a freely available code for cosmological N-body/SPH simulations written by Volker Springel at the Max Planck Institute for Astrophysics. This article describes version 2 of GADGET (known as GADGET-2).
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A gadget is a device or an appliance that has a useful specific practical purpose and function but is often thought of as a novelty. Gadgets are invariably considered to be unusually or cleverly designed than normal technology at the time of their invention. Gadgets are sometimes also referred to as gizmos. In some circles the distinction between a gadget and a gizmo is that a gizmo has moving parts, whereas a gadget need not have them. For example, a digital watch would be a gadget, while an analog watch would be a gizmo. Thus a gizmo is essentially a mechanical gadget.
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Noun
1. a device that is very useful for a particular job
(synonym) appliance, contraption, contrivance, convenience, gizmo, gismo, widget
(hypernym) device
(hyponym) gadgetry

n. gadget, gimmick; thingumajig

n. gadget, contrivance, accessory; giveaway, free prize