Apparatus/ˌæpəˈrætəs/ Definition 1 of 4Pro Tip 1/3Context Specific The term 'apparatus' often refers to complex setups, not simple tools. The lab was equipped with a sophisticated apparatus for analyzing samples. Pro Tip 2/3Not a Gadget 'Apparatus' usually suggests a system or set, not a single gadget. She adjusted the diving apparatus before exploring the coral reef. Pro Tip 3/3Professional Use 'Apparatus' is generally used in formal or professional contexts. The firefighters quickly deployed their apparatus to tackle the blaze.