He then committed several acts of brazen ____________.

Effrontery [Uncountable noun]
English Meaning: Insolent or impertinent behavior.
Bangla Meaning: ঔদ্ধত্য; নির্লজ্জ সাহস।
 
• Synonyms: Shamelessness (লজ্জাহীনতা), Impoliteness (অশিষ্টতা), Disrespect (অসম্মান; অশ্রদ্ধা), Arrogance (অহমিকা)।
• Antonyms: Timidity (ভীরুতা), Fear (ভয়), Cowardice (কাপুরুষতা), Shame (লজ্জা), Kindness (দয়ালু)।

Other Forms:
- [Countable noun] (Plural) effronteries).

Example Sentence: 
1. He then committed several acts of brazen effrontery.
2. The little squirt had the effrontery to deny eating any cookies, even with the crumbs still on his lips.

Meaning of other words:
- Savant (অত্যন্ত পণ্ডিতব্যক্তি)।
- Destitution (দুঃস্থতা; চরম দারিদ্র্য)।
- Susceptibility (সংবেদনশীলতা)।

Source: 
1. Accessible Dictionary by Bangla Academy
2. Cambridge Dictionary 
3. Website Lecture