transcription, транскрипция: [ ʌnənaʊnst ]
If someone arrives or does something unannounced , they do it unexpectedly and without anyone having being told about it beforehand.
He had just arrived unannounced from South America...
My first night in Saigon I paid an unannounced visit to my father’s cousins.
ADJ : usu ADJ after v , ADJ n , also v-link ADJ