(transitive or intransitive) To produce an appropriate physical effect; to issue in the result designed by nature; especially (medicine) to take appropriate effect on the human system.

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Sense（3）

(transitive or intransitive) To act or produce effect on the mind; to exert moral power or influence.

The Virtues of private Perſons, how Bright and Exemplary ſoever, operate but on Few; on thoſe only who are near enough to obſerve, and inclin'd to imitate them: their ſphere of Action is narrow, and their Influence is confin'd to it.

Google Translation / DeepL Translation

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Sense（4）

(medicine, transitive or intransitive) To perform some manual act upon a human body in a methodical manner, and usually with instruments, with a view to restore soundness or health, as in amputation, lithotomy, etc.

The surgeon had to operate on her heart.

Google Translation / DeepL Translation

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Sense（5）

(transitive or intransitive) To deal in stocks or any commodity with a view to speculative profits.

Sense（6）

(transitive or intransitive) To produce, as an effect; to cause.

We live our lives in three dimensions for our threescore and ten allotted years. Yet every branch of contemporary science, from statistics to cosmology, alludes to processes that operate on scales outside of human experience: the millisecond and the nanometer, the eon and the light-year.

Google Translation / DeepL Translation