Recent scandals have shaken many people's belief in politicians. The word 'Belief' is -

• Belief: [noun]
English meaning: the feeling of being certain that something exists or is true.
Bangla meaning: বিশ্বাস; আস্থা; প্রত্যয়।

Example: 
- Recent scandals have shaken many people's belief in politicians.
Bangla meaning: সাম্প্রতিক কেলেঙ্কারিগুলো অনেক মানুষের রাজনীতিবিদদের প্রতি বিশ্বাস নড়বড়ে করে দিয়েছে।

Other form: 
- Believe: [verb]
Meaning: to think that something is true, correct, or real.

- Believable: [adjective]
Meaning: If something is believable, it seems possible, real, or true.

- Believably: [adverb]
Meaning: in a way that seems possible, real, or true.

Source: Cambridge Dictionary.