Equipment, apparatus, machinery, paraphernalia, outfit, tackle, gear, matéiel are comparable when they mean all the things that are used in a given work or are useful in effecting a given end.
Equipment usually covers everything needed for efficient operation or efficient service except the personnel; thus, the equipment for a polar expedition would include not only the vessels, instruments, and implements required but also the sleds, dogs, and supplies (as clothing, food, and medicines).
Sometimes equipment is more limited in its application; thus, in railroading it covers only the rolling stock and not the roadbed and stations. In extended use equipment is also employed in reference to persons and covers the qualities and skills necessary to their efficiency or competency in a given kind of work.
Apparatus usually covers the instruments, tools, machines, and appliances used in a given craft or profession or in a specific operation or the equipment used in a recreation or sport; thus, the apparatus of a dentist includes all the mechanical and electrical devices he uses in his professional work; the apparatus of a laboratory, as distinguished from its equipment, consists of all the mechanical requisites for carrying on operations or experiments.
When used in reference to persons or employments not requiring mechanical devices, apparatus denotes all the external aids useful in prosecuting a particular kind of work; thus, the apparatus of a scholar in Old English includes the reference books (as texts, glossaries, and bibliographies) that he finds essential to or helpful in his investigations.
Machinery covers all the devices, means, or agencies which permit a thing (as an organism, a government, an institution, or a law) to function or which enable it to accomplish its ends (as a movement, a political party, or propaganda).
Paraphernalia usually suggests a collection of the miscellaneous articles or belongings that constitute the usual accompaniments (often the necessary equipment) of a person or group of persons in a particular employment or activity.
The word may be slightly contemptuous and imply a trivial or worthless character to the items included.
Outfit is sometimes interchangeable with equipment, but it has a slightly less formal flavor and is preferred when the latter term might seem pretentious. It often specifically suggests wearing apparel and other necessities for a journey, a school year, or a new employment.
Tackle is also less formal than apparatus, which otherwise it closely resembles.
Gear is variously used, sometimes approaching equipment or sometimes apparatus or again outfit, or wearing apparel. It is also occasionally the most general of these terms and equivalent to one’s belongings collectively.
Matériel is used in industry and in military affairs as a comprehensive and unambiguous term that covers everything but the personnel.