privy (adj.)youdaoicibaDictYouDict[privy 词源字典]
"private," early 13c., from Old French privé "friendly, intimate; a private place," from Latin privatus "private, personal" (see private (adj.)). Meaning "participating in (a secret)" (usually with to) is attested from late 14c. Related: Privily. Privy Council is from c. 1300 in a general sense; specifically of the British government, first attested late 14c., as consaile priue. Privy member "organ of sex" is from late 13c.[privy etymology, privy origin, 英语词源]
secretary (n.)youdaoicibaDictYouDict
late 14c., "person entrusted with secrets," from Medieval Latin secretarius "clerk, notary, confidential officer, confidant," a title applied to various confidential officers, noun use of adjective meaning "private, secret, pertaining to private or secret matters" (compare Latin secretarium "a council-chamber, conclave, consistory"), from Latin secretum "a secret, a hidden thing" (see secret (n.)).

Meaning "person who keeps records, write letters, etc.," originally for a king, first recorded c. 1400. As title of ministers presiding over executive departments of state, it is from 1590s. The word also is used in both French and English to mean "a private desk," sometimes in French form secretaire. The South African secretary bird so called (1786) in reference to its crest, which, when smooth, resembles a pen stuck over the ear. Compare Late Latin silentiarius "privy councilor, 'silentiary," from Latin silentium "a being silent."