Hydrocarbon, any of a class of organic chemical compounds composed only of the elements carbon (C) and hydrogen (H). The carbon atoms join together to form the framework of the compound; the hydrogen atoms attach to them in many different configurations. Hydrocarbons are the principal constituents of petroleum and natural gas.
Use slab in a sentence. 1  a piece that is flat, broad, and fairly thick: a slab of concrete, a slab of bread.  any of the rough, outer pieces cut from a log, as in sawing it into lumber.
trench. n. 1. A deep furrow or ditch. 2. A long narrow ditch embanked with its own soil and used for concealment and protection in warfare. 3. A long, steep-sided valley on the ocean floor. v. trenched, trenchÂ·ing, trenchÂ·es. v. tr. 1. To dig or make a trench or trenches in (land or an area, for example).