Unannounced rhymes with:
announced, mispronounced, pronounced, announced, denounced, mispronounced, pronounced, renounced, announced, bounced, denounced, mispronounced, pounced, pronounced, renounced, trounced
Unannounced sounds like:
umscheid, umstead, unangst, unassisted, unchecked, uncoat, uncoated, uncouth, unctad, uncut, unhinged, unionist, unionized, unissued, unjust, unmanaged, unmasked, unmixed, unquote, unsaid, unscathed, unseat, unseated, unset, unstated, unsteady, unsuited, unswayed, unused, unwashed