Of a newspaper column: in which people attempt to find friends of the opposite sex.

A hero of westerns who wore a mask. / A solitary, sometimes mysterious or heroic, person.

(idiomatic) An individual person who acts on his or her own initiative, without partners, especially one who has sole responsibility for doing something questionable, confidential, or iniquitous.

plural of no-lone zone

One who acts alone. / A terrorist who acts on their own, without being part of a larger organized group or cell.

plural of lone wolf

plural of lone wolfer

Yearning for affection and companionship.

The quality of being lonely-hearted.

plural of lone pair