Antonyms for Loose (opposite meaning)
WordNet sense 1 (deprive of freedom; take into confinement):
confine
WordNet sense 2 (closely constrained or constricted or constricting):
tight
WordNet sense 3 (closely and firmly united or packed together):
compact, compact
WordNet sense 4 (make stiff or stiffer):
stiffen
WordNet sense 5 (firmly attached):
affixed
From the ODE community, based on WordNet
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