The Collaborative International Dictionary of English v.0.48:

boondocks \boondocks\ n.
   a remote and undeveloped area; -- sometimes used
   deprecatingly.

   Syn: backwoods, back country, hinterland.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

boondocks
    n 1: a remote and undeveloped area [syn: backwoods, back
         country, boondocks, hinterland]

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "boondocks":
   China, Darkest Africa, God knows where, Greenland, North Pole,
   Outer Mongolia, Pago Pago, Pillars of Hercules, Siberia,
   South Pole, Thule, Tierra del Fuego, Timbuktu, Ultima Thule, Yukon,
   afforestation, antipodes, arboretum, back country, backcountry,
   backwash, backwater, backwoods, boondock, borderland, brush, bush,
   bush country, bushveld, chase, climax forest, cloud forest,
   dendrology, forest, forest land, forest preserve, forestry,
   forests, fringing forest, frontier, gallery forest,
   godforsaken place, greenwood, hanger, hinterland, index forest,
   jumping-off place, jungle, jungles, national forest, nowhere,
   outback, outer space, outpost, outskirts, palmetto barrens, park,
   park forest, pine barrens, pole, primeval forest,
   protection forest, rain forest, reforestation, scrub, scrubland,
   selection forest, shrubland, silviculture, sprout forest,
   stand of timber, state forest, sticks, the Great Divide,
   the South Seas, the boondocks, the bush, the moon, the sticks,
   the tullies, timber, timberland, timbers, tree veld,
   uninhabited region, up-country, virgin forest, virgin land,
   virgin territory, wasteland, wild West, wilderness, wilds,
   wildwood, wood, woodland, woodlands, woods