[Middle English, from Old French, from Latin sēcrētus from past participle of sēcernere, to set aside : sē-, apart + cernere, to separate.]

Synonyms: secret, stealthy, covert, clandestine, furtive, surreptitious, underhand. These adjectives mean deliberately hidden from view or knowledge. Secret is the most general: a desk with a secret compartment; a secret marriage; secret negotiations. Stealthy suggests quiet, cautious deceptiveness intended to escape notice: heard stealthy footsteps on the stairs. Covert describes something that is not overt but is concealed or disguised: Students protested covert actions undertaken by the CIA. Clandestine implies stealth and secrecy for the concealment of an often illegal or improper purpose: a clandestine tryst; clandestine intelligence operations. Furtive suggests the slyness, shiftiness, and evasiveness of a thief: a menacing and furtive look to his eye. Something surreptitious is stealthy, furtive, and often unseemly or unethical: took a surreptitious glance at his watch; the surreptitious mobilization of troops in preparation for a sneak attack. Underhand implies unfairness, deceit, fraud, or slyness as well as secrecy: achieved success in business only by resorting to underhand methods.