single-case

The compound adjective "single-case" is a modern formation, primarily used in technical and analytical contexts. Its first element, "single," traces back to the Latin singulus, meaning "one alone, individual," which itself may derive from the Proto-Indo-European root sem- meaning "one." The second element, "case," originates from Latin casus, meaning "a fall, chance event, or grammatical inflection," from the verb cadere (to fall). The semantic evolution from a physical "fall" to an abstract "occurrence" or "instance" is clear. Combined, the morphemes literally mean "one instance," a logic directly preserved in its modern use to describe something limited to or focused on a solitary example or scenario, especially in fields like psychology, law, and software engineering.

Structure: single (one) + case (instance) - single: From Latin singulus (one, individual). Functional role: Adjective-forming root, meaning "one". - case: From Latin casus (a falling, an occurrence, a grammatical case). Functional role: Noun-forming root, meaning "instance, situation, or occurrence".