In"let (?), n.
1.
A passage by which an inclosed place may be entered; a place of ingress; entrance.
Doors and windows,inlets of men and of light.
Sir H. Wotton.
2.
A bay or recess,as in the shore of a sea, lake, or large river; a narrow strip of water running into the land or between islands.
3.
That which is let in or inland; an inserted material.
⇒ Inlet is also usewd adjectively,as in inlet pipe, inlet valve, etc.
© Webster 1913.