transcription, транскрипция: [ ʌndri:md ɒv, AM - ʌv ]
Note: in BRIT, also use 'undreamt of'
If you describe something as undreamed of , you are emphasizing that it is much better, worse, or more unusual than you thought was possible.
This new design will offer undreamed-of levels of comfort, safety and speed...
They have freedoms that were undreamed-of even ten years ago.
ADJ [ emphasis ]