Synonyms for Unattached (same or very similar meaning)
WordNet sense 1 (not joined or linked together):
unconnected
WordNet sense 2 ((of animals) able to swim about; not attached):
free-swimming
WordNet sense 3 (having freedom to move about):
vagile
WordNet sense 4 (not associated in an exclusive sexual relationship):
uncommitted
From the ODE community, based on WordNet
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