Theft, larceny, robbery, burglary mean the act or crime of stealing, though they have differences in legal application. The same differences in implications and applications are observable in the agent nouns thief, larcener or larcenist, robber, burglar , denoting one who steals.
Theft and thief are the most general and the least technical of these terms; they imply the taking and removing of another’s property usually by stealth or without his knowledge and always without his consent. The terms are often so broad that they may include reference to any taking of another’s property without his consent (as by pilfering, purloining, swindling, embezzling, or plagiarizing).
Larceny and the less common agent nouns larcener and larcenist are legal terms implying direct theft but excluding such specialized forms as swindling, embezzlement, and plagiarizing. The terms connote an unlawful or felonious act, a removal of another’s property from the place where it belongs, and complete possession, even for a moment, by the thief.
Grand larceny and petty larceny are common in ordinary use as indicating respectively a theft of an appreciable amount and a theft of a negligible amount.
Robbery and robber in their precise legal use imply the taking of another’s property from his person or in his presence by means of violence or intimidation.
Burglary and burglar in legal use imply a breaking and entering with an intent to commit a felony, usually that of larceny or robbery. In the laws of different states and nations the detailed specifications of the crime, for example, the time of occurrence (nighttime often being stipulated) or the actual commission of the felony, may or may not be considered material to the charge.