Daimyo (大名) is a generic term that refers to a powerful Japanese feudal lord, landlord, subordinate only to the Shogun.
They were the powerful landlords in Japan, who ruled most of Japan from their vast hereditary properties between the X and XIX centuries.
During this period, Japan was divided into several autonomous territories. They were controlled by feudal lords (daimyo), with the support of samurai. Daimyo often hired samurai to protect their land and paid the samurai with land or food. Relatively few daimyos could afford to pay the samurai in cash.
In the XII century, some daimyos were more powerful than the emperor himself. This was at least until its decline at the beginning of the Meiji period.
Meaning, DAI (大) literally means “big” and MYO means myōden (名 田), which means private land.