People who are needy don't have enough of life's necessities, like money, food, water, education, or shelter. Many charities collect money that helps needy people.
Truly needy people go without food or warmth, for example, and often need help from others. As a group, these people are sometimes referred to as "the needy." A more lighthearted way to use the adjective is to mean "demanding or difficult." This type of needy person requires frequent reassurance or emotional support: "She's a good friend, but she can be so needy sometimes."