The term Single is a relationship term which means that a person is not married. It is also commonly used to indicate more narrowly that the person is not in an exclusive romantic relationship. Those who are single are often referred to as bachelors (men) and bachelorettes (women).

People who are single typically engage in "dating" (human courtship) to find a spouse. The term Quirkyalone refers to someone who enjoys being single and thus prefers to wait for the right person to come along rather than date indiscriminately.

Loneliness, however, can occur for many singles who cannot find anyone for "dating", especially for those who have experienced loss of companionship through divorce. (However, some "alone" people appreciate the solitude, using the time to get their life in order.)