is a specific kind of: nonworker.

is a broader term that covers: clock watcher | couch potato | dallier, dilly-dallier, dillydallier, lounger, mope | dawdler, drone, laggard, lagger, poke, trailer | daydreamer, woolgatherer | goldbrick, good-for-naught, good-for-nothing, goof-off, ne'er-do-well, no-account | lazybones | lie-abed, slugabed | loon | shirker, slacker | slug, sluggard | spiv | sunbather | trifler | whittler ... show more.

derivation: bum, cadge, grub, mooch, sponge | idle, laze, slug, stagnate | arse about, arse around, bum, bum about, bum around, frig around, fuck off, loaf, loll, loll around, lounge about, lounge around, waste one's time | do-nothing.