Real Dictionary

start
a unit that consists of three adjacent bases on a DNA molecule and that determines the position of a specific amino acid in a protein molecule during protein synthesis [...]
the first or first part of a series of actions or operations, a journey, etc [...]
the substance of which a thing is made or composed; component or constituent matter [...]
verb: If you start an engine, car, or machine, or if it starts, it begins to work.
verb: If you start by doing something, or if you start with something, you do that thing first in a series of actions.
verb: If you start to do something, you do something that you were not doing before and you continue doing it.
verb: If you start, your body suddenly moves slightly as a result of surprise or fear.
verb: When someone starts something such as a new business, they create it or cause it to begin.
verb: When something starts, or if someone starts it, it takes place from a particular time.
verb: You use start to say what someone's first job was. For example, if their first job was that of a factory worker, you can say that they started as a factory worker.