The phrase "tough-on-crime" is a modern political compound adjective originating in late 20th-century English. It is formed by combining the native English adjective "tough," with its core sense of unyielding harshness, the simple preposition "on" to denote direction, and the noun "crime," a word of Latin origin via French denoting serious wrongdoing. The logic of the construction is transparent and literal: a stance that is severe regarding crime. This phrase encapsulates a specific political ideology by framing criminal justice policy in stark, adversarial terms, where "toughness" is presented as the primary and virtuous response to criminal acts.

Structure: tough (hard, severe) + on (directed at) + crime (illegal act) - tough: From Old English tōh (strong, firm, tenacious). In this compound, it functions as an adjective meaning severe or uncompromising. - on: From Old English on, an (in, into, onto, upon, at, to). In this compound, it functions as a preposition indicating the target or focus of the severity. - crime: From Old French crimne (crime, sin), from Latin crīmen (charge, indictment, offense). In this compound, it functions as a noun specifying the object of the policy.