These words are used to refer to people or places which are apart from others. Lonely is a broad term describing a state of mind which is induced by lack of companionship or the kind of sympathy which companionship can provide. A lonely feeling can range from the mild sadness engendered by a casual instance of solitude to the great unhappiness and depression one might feel after a long period of separation from or lack of meaningful relationship with other people: a lonely young sailor feeling sorry for himself because his date had stood him up; a lonely spinster whose eccentricities had robbed her of the opportunity for anything but the most impersonal kind of social contact. Lonely stretch of beach where it was possible to bathe in the nude. In reference to places, lonesome intensifies the meaning of lonely to suggest a place not merely deserted but having an air of melancholy about it: a house she had always thought of as over-crowded but which was lonesome and cavernous when her children grew up and went out on their own. In its description of people lonesome is again a stronger word than lonely but is slightly less formal in tone. It often suggests the dejection felt when one is faced with the absence of someone to whom one is or has been very close: a merchandising executive who never got over being lonesome when he had to leave his family for business travel; lonesome for a pet dog that he’d raised from a pup and that had just died.

Forlorn is more specific than either of the two preceding words in its suggestion that the person described as such is alone because he has been deserted or abandoned: wretched and forlorn in the half-empty waiting room, despairing of the arrival of a friend who had promised to meet her but who was already three hours late. The place referred to as forlorn seems also to have been deserted and has the air of loneliness that characterizes remote or abandoned dwelling and locales: a once fashionable resort that was now a forlorn ghost town.

Solitary can mean lonely and can describe a person or place: the solitary feeling one sometimes experiences in the middle of a crowded room; the solitary desert. But solitary , in a way that none of the other words in this group can, may suggest an aloneness that has been chosen rather than imposed. Thus, a person who is solitary by nature often prefers contemplation to companionship, and a solitary traveller prefers travelling alone to being with a large group on an organized tour.