say-so

The compound 'say-so' is a transparent English formation from the common verb 'say' and the adverb 'so'. It emerged in the late 17th century, directly reflecting the literal action of declaring something to be so. The term's logic is inherently procedural: the authority to declare a state of affairs ('say') and have it accepted as true or valid ('so'). Over time, this concrete sense of verbal declaration evolved into the more abstract meanings of personal authority or an unsupported assertion, capturing both the power behind a statement and the potential emptiness of its content.

Structure: say (to utter words) + so (in that manner) - say: From Old English 'secgan' (to utter, tell). Functional role: Verbal root. - so: From Old English 'swā' (in that way, thus). Functional role: Adverbial particle.