Pronunciation: (lōn'sum),[key] —adj. 1. depressed or sad because of the lack of friends, companionship, etc.; lonely: to feel lonesome. 2. attended with or causing such a state or feeling: a lonesome evening at home. 3. lonely or deserted in situation; remote, desolate, or isolated: a lonesome road.
—n. on or by one's lonesome.Also,Scot.,by one's lane.Informal.alone: She went walking by her lonesome.