The word 'Allegiance' is a/an -

• The word 'Allegiance' is an - Noun.

• Allegiance (noun)
English Meaning: the fidelity owed by a subject or citizen to a sovereign or government.
Bangla Meaning: কর্তব্য; নিষ্ঠা; বিশ্বস্ততা; আনুগত্য।

Other forms: 
- allegiant - Adjective.

Example Sentence:
- The knight pledged his allegiance to the king, vowing to serve him faithfully.

Source:
1. merriam-webster.
2. Accessible Dictionary by Bangla Academy.