Wordnet 3.0
NOUN (1)
1.
one who behaves lightly or not seriously;
The Collaborative International Dictionary of English v.0.48:
Trifler \Tri"fler\, n.
One who trifles. --Waterland.
[1913 Webster]
WordNet (r) 3.0 (2006):
trifler
n 1: one who behaves lightly or not seriously
Moby Thesaurus II by Grady Ward, 1.0:
63 Moby Thesaurus words for "trifler":
Sunday painter, amateur, bungler, clock watcher, coquet,
criticaster, dabbler, dabster, dallier, dawdle, dawdler, diddler,
dilettante, dillydallier, disregarder, do-nothing, dodger,
dolittle, doodler, faineant, flirt, fribble, gentleman of leisure,
goldbrick, goldbricker, goof-off, grammaticaster, half scholar,
idler, ignorer, laggard, lingerer, loafer, loiterer, loller,
lotus-eater, lounger, lubber, malingerer, mope, moper, neglecter,
negligent, philologaster, philosophaster, piddler, potterer,
procrastinator, putterer, sciolist, shirker, slacker, slouch,
sloucher, sloven, slug, sluggard, slut, smatterer,
stick-in-the-mud, time killer, time waster, waiter on Providence