Copy and paste Long Dash Symbol (—). Check Alt Codes and learn how to make specific symbols on the keyboard. LONG definition: having considerable linear extent in space. See examples of long used in a sentence. To strongly crave or desire something is to long for it. No matter how healthful your diet is, you'll still occasionally long for chocolate, cookies, and cake. The adjective long describes something that stretches over a large distance. long, yearn, hanker, pine, hunger, thirst mean to have a strong desire for something. long implies a wishing with one's whole heart and often a striving to attain. yearn suggests an eager, restless, or painful longing. hanker suggests the uneasy promptings of unsatisfied appetite or desire. 1. A long time: This won't take long. 2. Linguistics A long syllable, vowel, or consonant. 3. One who acquires holdings in a security or commodity in expectation of a rise in price. LONG definition: 1. continuing for a large amount of time: 2. being a distance between two points that is more than…. Learn more. Wide may be used instead of long when referring to a left-to-right horizontal dimension, or to a horizontal dimension shorter than that described as long (for example, a river that is wide and long).