Look in the user's manual at the parts break down.
What nomenclature do they give the part?
On the 1911, the accepted term is slide stop. As a "stop", it should not be used to release the slide.
If the book calls it a release, then release the with it.
(And yes, I know a lot of people use the 1911 slide stop as a release with no ill affects so far, but it is a practice that should be discouraged.)
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