What is the secret, and what is its relation to privacy? Some musings, on reading Clare Birchall’s 2011 paper “Transparency Interrupted” in Theory, Culture & Society.

Etymology:

secret (n.)late 14c., from Latin secretus “set apart, withdrawn, hidden,” past participle of secernere “to set apart,” from se- “without, apart,” properly “on one’s own” (from PIE *sed-, from root *s(w)e-; see idiom) + cernere “separate” (see crisis). As an adjective from c.1400. Secret agent first recorded 1715; secret service is from 1737; secret weapon is from 1936.

Of course linked to this is the word private:

private (adj.)late 14c., “pertaining or belonging to oneself, not shared, individual; not open to the public;” of a religious rule, “not shared by Christians generally, distinctive; from Latin privatus “set apart, belonging to oneself (not to the state), peculiar, personal,” used in contrast to publicus, communis; past participle of privare “to separate, deprive,” from privus “one’s own, individual,” from PIE*prei-wo-, from PIE *prai-, *prei-, from root *per- (1) “forward, through” (see per). Old English in this sense…