A person who writes dictionaries is called –

A person who writes dictionaries is called Lexicographer.

• Lexicographer
- English Meaning: an author or editor of a dictionary.
- Bangla Meaning: অভিধান রচয়িতা বা সংকলক।

• Other options:
- a writer of a biography – Biographer জীবনীকার।
- a person who writes their own biography – Autobiographer ( আত্মজীবনী-রচয়িতা)।
- one that makes maps – Cartographer (মানচিত্রকর।)।

Source:
1. Accessible Dictionary.
2. Merriam-Webster Dictionary.