private_eye has definitions from the field of work
1
[ noun ] (work) someone who can be employed as a detective to collect information

Used in print

(R. F. Shaw, "The `Private Eye`"...)

The mythological private_eye differs from his counterpart in real life in two essential ways .

Whatever his original assignment , the fictional private_eye ends_up by investigating and solving a crime , usually a murder .

By_virtue_of his self-reliance , his individualism and his freedom from external restraint , the private_eye is a perfect embodiment of the middle_class conception of liberty , which amounts to doing what you please and let_the_devil_take_the_hindmost .

In_short , the fictional private_eye is a specialized version of Adam_Smith 's ideal entrepreneur , the man whose private ambitions must always and everywhere promote the public welfare .

Sherlock_Holmes , the ancestor of all private_eyes , was born during the 1890 s .

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