Everglades (n.)

Old English æfre "ever, at any time, always;" of uncertain origin, no cognates in any other Germanic language; perhaps a contraction of a in feore, literally "ever in life" (the expression a to fore is common in Old English writings). First element is almost certainly related to Old English a "always, ever," from Proto-Germanic *aiwi-, extended form of PIE root *aiw- "vital force, life; long life, eternity." Liberman suggests second element is comparative adjectival suffix -re.

Sometimes contracted to e'er in dialect and poetry. Ever began to be used in late Old English as a way to generalize or intensify when, what, where, etc. The sense evolution was from "at any time at all, in any way" to "at any particular time; at some time or another; under any circumstances." Ever so "to whatever extent" is recorded by 1680s. Expression did you ever? (implying "see/do/hear of such a thing") attested by 1840.

"clear, open space in a woods," late 14c., of uncertain origin, perhaps from Middle English glode (c. 1300), from Old Norse glaðr "bright" (see glad). If so, the original meaning could be "bright (because open) space in a wood" (compare French clairière "glade," from clair "clear, bright;" German Lichtung "clearing, glade," from Licht "light"). American English sense of "tract of low, marshy grassland" (as in Everglades) recorded by 1789, perhaps 1724 in place names (in Maryland).