omnivorous ungulate pachydermatous mammal of Africa, 1560s, from Late Latin hippopotamus, from Greek hippopotamus "riverhorse," an irregular formation from earlier ho hippos potamios "the horse of the river"), from hippos "horse" (from PIE root *ekwo- "horse") + adjective from potamos "river, rushing water" (see potamo-). Replaced Middle English ypotame (c. 1300), which is from the same source but deformed in Old French. Glossed in Old English as sæhengest. Translated as river-horse in Holland's Pliny (1601).
Ypotamos comen flyngynge. ... Grete bestes and griselich ["Kyng Alisaunder," c. 1300]
Related to have (Old English habban "to hold, possess"). Meaning "to throw" is from 1590s. Nautical meaning "haul or pull" in any direction is from 1620s. Intransitive use from early 14c. as "be raised or forced up;" 1610s as "rise and fall with alternate motion." Sense of "retch, make an effort to vomit" is first attested c. 1600. Related: Heaved; heaving. Nautical heave-ho was a chant in lifting (c. 1300, hevelow).
"variety of magnetite characterized by its power of attracting iron and steel," mid-15c. (earlier magnes, late 14c.), from Old French magnete "magnetite, magnet, lodestone," and directly from Latin magnetum (nominative magnes) "lodestone," from Greek ho Magnes lithos "the Magnesian stone," from Magnesia (see magnesia), region in Thessaly where magnetized ore was obtained. Figurative sense of "something which attracts" is from 1650s.
It has spread from Latin to most Western European languages (German and Danish magnet, Dutch magneet, Italian, Spanish, Portuguese magnete), but it was superseded in French by aimant (from Latin adamas; see adamant (n.)). Italian calamita "magnet" (13c.), French calamite (by 16c., said to be from Italian), Spanish caramida (15c., probably from Italian) apparently is from Latin calamus "reed, stalk or straw of wheat" (see shawm) "the needle being inserted in a stalk or piece of cork so as to float on water" [Donkin]. Chick magnet attested from 1989.
definite article, late Old English þe, nominative masculine form of the demonstrative pronoun and adjective. After c.950, it replaced earlier se (masc.), seo (fem.), þæt (neuter), and probably represents se altered by the th- form which was used in all the masculine oblique cases.
Old English se is from PIE root *so- "this, that" (source also of Sanskrit sa, Avestan ha, Greek ho, he "the," Irish and Gaelic so "this"). For the þ- forms, see that. The s- forms were entirely superseded in English by mid-13c., excepting a slightly longer dialectal survival in Kent. Old English used 10 different words for "the," but did not distinguish "the" from "that." That survived for a time as a definite article before vowels (that one or that other).
Adverbial use in the more the merrier, the sooner the better, etc. is a relic of Old English þy, the instrumentive case of the neuter demonstrative (see that).