Why is the ninth month called September?
"pointed stick or post," Old English staca, from Proto-Germanic *stakon (cf. Old Norse stiaki, Dutch staak, German stake), from PIE root *steg- "pole, stick." The Germanic word has been borrowed in Spanish (estaca), Old French (estaque), and Italian stacca) and was borrowed back as attach. Meaning "post upon which persons were bound for death by burning" is recorded from c.1200. Stake-body as a type of truck is attested from 1907. In pull up stakes, "The allusion is to pulling up the stakes of a tent" [Bartlett].
early 14c., "to mark (land) with stakes," from stake (n.1). Hence, to stake a claim (1857). Meaning "to risk, wager" is attested from 1520s, probably from notion of "post on which a gambling wager was placed," though Weekley suggests "there is a tinge of the burning or baiting metaphor" in this usage. Meaning "to maintain surveilance" (usually stake out) is first recorded 1942, American English colloquial, probably form earlier sense of "mark off territory." Related: Staked; staking.