Thakur means God, Deity, Idol, Overlord, Lord, Leader or Master, a man deserving respect or reverence, an elder, a spiritual guide, a guru, priest, teacher, a Brahman or, a Brahman employed as a cook.
Thakur and thākura are the words derived from the Sanskrit word thakkura meaning "administrator" or jamindaar. Used as a term of respect meaning "chief", "lord", or "master". Also the name of a Kshatriya family in Bengal whose members have Anglicised their name Thakur. Thakur as a Bengali surname is derived from "Thakurmashai" or 'holy sir' for any Bengali Brahmins and also for someone of high spiritual esteem.
Thakur is also an Indian feudal and colonial title in Hindi.
References
Thakur (Bengali surname) Wikipedia(Text) CC BY-SA