PIE*komのnearest, besideから。語源的にはge-, com-と同じ。
They lay soe close together, they made me much to wonder;As a noun meaning "semen or other product of orgasm" it is on record from the 1920s. The sexual cum seems to have no connection with Latin cum, the preposition meaning "with, together with," which is occasionally used in English in local names of combined parishes or benifices (such as Chorlton-cum-Hardy), in popular Latin phrases (such as cum laude), or as a combining word to indicate a dual nature or function (such as slumber party-cum-bloodbath).
I knew not which was wether, until I saw her under.
Then off he came, and blusht for shame soe soon that he had endit;
Yet still she lies, and to him cryes, "one more and none can mend it."