Synonyms for Usable (same or very similar meaning)
WordNet sense 1 (capable of being put to use):
useable
WordNet sense 2 (being of use or service):
useful, utile
WordNet sense 3 (fit or ready for use or service):
functional, operable, operational
WordNet sense 4 (convenient for use or disposal):
available
WordNet sense 5 (free or available for use or disposition):
disposable
From the ODE community, based on WordNet
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