un ‧ speak ‧ a ‧ ble /ʌnˈspiːkəb ə l/ BrE AmE adjective
[ Word Family: adjective : ↑ unspeakable , ↑ speechless , ↑ outspoken , ↑ spoken ≠ ↑ unspoken ; noun : ↑ speaker , ↑ speech ; verb : ↑ speak ; adverb : ↑ unspeakably ]
1 . used for emphasizing how bad someone or something is:
an unspeakable tragedy
2 . literary unspeakable feelings are so extreme that it is impossible to describe them:
unspeakable joy
—unspeakably adverb