Synonyms and related words :
breakaway, imageless, involuntary, offbeat, rare, recherche, sui generis, uncommon, unconceived, unconceptualized, unconscious, unconsidered, uncustomary, undescried, undesigned, undreamed-of, unexpected, unfamiliar, unguarded, unguided, unheard-of, unheeded, unimaged, unimagined, unintended, unintentional, unique, unmarked, unmeant, unmeditated, unminded, unmissed, unnoted, unnoticed, unobserved, unordinary, unperceived, unplanned, unpremeditated, unprompted, unpurposed, unregarded, unremarked, unseen, unthinking, unusual, unwitting, unwonted