See HOV lane
- Heavy oil
noun 1. a hydrocarbon mixture, heavier than water, distilled from coal tar
noun 1. either of the two stable isotopes of oxygen having mass numbers of 17 and 18.
- Heavy particle
heavy particle A subatomic particle with relatively high mass, especially a baryon.
noun 1. Informal. intense that involves mutual stimulation of the genitals but not sexual intercourse. noun stimulating sexual contact between two people just short of intercourse Examples In high school, teenagers experiment with heavy petting. Word Origin 1952 noun phrase Very passionate kissing, fondling, etc, stopping short of the sex act proper (1940s+)