ambitious (similar term)
challenging (similar term)
arduous (similar term)
awkward (similar term)
embarrassing (similar term)
sticky (similar term)
unenviable (similar term)
baffling (similar term)
elusive (similar term)
knotty (similar term)
problematic (similar term)
problematical (similar term)
tough (similar term)
catchy (similar term)
tricky (similar term)
delicate (similar term)
ticklish (similar term)
touchy (similar term)
fractious (similar term)
hard-fought (similar term)
herculean (similar term)
nasty (similar term)
tight (similar term)
rocky (similar term)
rough (similar term)
rugged (similar term)
tough (similar term)
serious (similar term)
tall (similar term)
thorny (similar term)
troublesome (similar term)
trying (similar term)
vexed (similar term)
demanding (related term)
effortful (related term)
hard (related term)
easy (antonym)