"open large-mouthed vessel," mid-14c., from Old Norse bikarr or Middle Dutch beker "goblet," probably (with Old Saxon bikeri, Old High German behhari, German Becher) from Medieval Latin bicarium, which is probably a diminutive of Greek bikos "earthenware jug, wine jar, vase with handles," also a measure, of uncertain origin. Sometimes said to be a Semitic word, perhaps a borrowing from Syrian buqa "a two-handed vase or jug," or from Egyptian b:k.t "oil flask." Form assimilated in English to beak. Originally a drinking vessel; the word is used from 1877 in reference to a similar glass vessel used in scientific laboratories.
O for a beaker full of the warm South,
Full of the true, the blushful Hippocrene,
With beaded bubbles winking at the brim,
And purple-stained mouth;
That I might drink, and leave the world unseen,
And with thee fade away into the forest dim:
[Keats, from "Ode to a Nightingale"]