The internal workings of a mechanism or system that are normally hidden from view(noun)
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Use "internals" in a sentence
"But what's really interesting, Tony, is when you look at what we call the internals in these polls."
"An examination of some of the internals from the latest Gallup survey of likely voters leads to the conclusion that these results are wildly implausible."
"In the case of the reactor vessel, a giant carbon-steel pot with a stainless-steel liner, the "internals" - the metal frame that held the core and channeled the water on its serpentine path-were chopped up with water jets and cutting tools."