Lonesome
Part of speech: adjective
Definition: unhappy due to being alone; lonely
Part of speech: noun
Definition: oneself alone
Example sentence: The moon is a friend for the lonesome to talk to.
Lonely
Part of speech: adjective
Definition: Of person, unhappy by feelings of loneliness.Of place, unfrequented by people; desolate.Of person, without companions; solitary.
Example sentence: Only the lonely know the way I feel tonight.