1.A close union or junction of bodies; a touching or meeting.
2.(Geom.) The property of two curves, or surfaces, which meet, and at the point of meeting have a common direction.
3.(Mining) The plane between two adjacent bodies of dissimilar rock.
4.(Electricity) A metallic conducting component of an electrical device connected to a circuit within and so situated that it may form a conducting pathway to an external power source or device when contacted by another conductor; as, the contact on a standard light bulb has the shape of a screw for easy insertion into the socket.
5.A person who serves to commmunicate information to or from one group to another, whether formally or informally; as, a good Washington reporter has contacts in the White House.
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