Antonyms for Easy (opposite meaning)
WordNet sense 1 (lacking a sense of security or affording no ease or reassurance):
uneasy
WordNet sense 2 (not easy; requiring great physical or mental effort to accomplish or comprehend or endure):
difficult, hard
WordNet sense 3 (with rapid movements):
apace, quickly, rapidly, speedily, chop-chop
From the ODE community, based on WordNet
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