LONG definition: 1. continuing for a large amount of time: 2. being a distance between two points that is more than…. Learn more. The adjective long describes something that stretches over a large distance. If you're trying to avoid a prolonged visit with your crazy Aunt Martha, you might decide to take the long way to her house. 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). LONG Building Technologies provides building automation, security systems, commercial HVAC service and parts, as well as building analytics. Definition of LONG in the Definitions.net dictionary. Meaning of LONG. What does LONG mean? Information and translations of LONG in the most comprehensive dictionary definitions resource on the web. Learn what long means with clear definitions, pronunciation, synonyms, and real-world examples. Simple explanations to help you use long correctly. Tired of saying long? This list of 100 vivid alternatives adds precision and style to your writing, including a few surprising picks you will want to steal. We deliver innovative, custom HVAC solutions across the state that meet the unique needs of your commercial building and keep your HVAC systems efficient and cost-effective. 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.