Manava Dharmashastra 1.90

1.90

vaṇikpathaḥ vaṇikkarmaṇā sthalapathavāripathādinā dhanārjanam upayujyamānadeśāntarīyadravyasannidhāpanaṃ yasya rājño viṣaye vasati | kusīdaṃ vṛddhyā dhanaprayogaḥ |

For the Vaiśya, tending of cattle, giving of gifts, sacrificing and studying; as also trade, money-lending and cultivating of land. (90).

Medhātithi’s commentary (manubhāṣya):
‘Trade,’—i.e., the acquiring of wealth by carrying on trade, on land and on water, and the importing of useful goods from foreign countries into the state of that king in whose kingdom he lives.

‘Money-lending’—giving out money on interest. (90).