Princeton's WordNet

1. incredibly, improbably, implausibly, unbelievably(adverb)

   not easy to believe

   "behind you the coastal hills plunge to the incredibly blue sea backed by the Turkish mountains"

2. unbelievably(adverb)

   in an unbelievable manner

   "he was unbelievably angry"

Kernerman English Learner's Dictionary

1. unbelievably(adverb)ˌʌn bɪˈli və bəl

   emphasizes how extreme sth is

   an unbelievably cold day

Wiktionary

1. unbelievably(Adverb)

   In a manner that one does not believe.

   He gestured unbelievably. Everyone knew he was faking being sick.

2. unbelievably(Adverb)

   To an extent not to be believed.

   His face turned unbelievably blue. We realized he was actually choking.

3. unbelievably(Adverb)

   Contrary to expectations, amazingly.

   Unbelievably, Rudy saved the man's life but got sued for breaking two of his ribs.

• ongelooflikAfrikaans
• بصورَةٍ لا تُصَدَّقArabic
• невероятноBulgarian
• inacreditavelmentePortuguese (BR)
• neuvěřitelněCzech
• unglaublichGerman
• utroligtDanish
• απίστευταGreek
• increíblementeSpanish
• uskumatultEstonian
• بطور باور نکردنیFarsi
• uskomattomanFinnish
• incroyablementFrench
• שֶׁלא לְהַאֲמִיןHebrew
• अविश्वसनीय रूप सेHindi
• nevjerojatnoCroatian
• hihetetlenülHungarian
• secara luar biasaIndonesian
• ótrúlegaIcelandic
• incredibilmenteItalian
• 信じられないほどJapanese
• 믿을 수 없게Korean
• neįtikėtinaiLithuanian
• neticamiLatvian
• yg luar biasaMalay
• ongelooflijkDutch
• utrolig, ubegripeligNorwegian
• niewiarygodniePolish
• بطور باور نکردنیPersian
• دنه منلو په توګهPashto
• incrivelmentePortuguese
• incredibil, de necrezutRomanian
• невероятноRussian
• neuveriteľneSlovak
• neverjetnoSlovenian
• neverovatnoSerbian
• otroligtSwedish
• อย่างไม่น่าเชื่อ; อย่างเชื่อถือไม่ได้Thai
• inanılmaz şekildeTurkish
• 難以置信地Chinese (Trad.)
• неймовірноUkrainian
• ناقابل يقين طور پرUrdu
• không thể tin đượcVietnamese
• 难以相信地Chinese (Simp.)