Synonyms for Unaccompanied (same or very similar meaning)
WordNet sense 1 (composed or performed by a single voice or instrument):
solo
WordNet sense 2 (cut off or left behind):
isolated
WordNet sense 3 (lacking companions or companionship):
alone, solitary
WordNet sense 4 (independent; not united or joint):
separate, separate
From the ODE community, based on WordNet
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