You use tall to describe things which are higher than usual, but which are also much higher than they are wide. So, for example, you talk about a tall tree or a tall chimney. Definition of tall adjective in oxford advanced learner's dictionary.

You use tall to ask or talk about the height of someone or something. How tall are you? I'm only 5ft tall, and i look younger than my age. I am already as tall as she is. Having a relatively great height; Of more than average stature: Tall grass.

Having a relatively great height; Of more than average stature: Tall grass. See examples of tall used in a sentence. In a tall organizational structure, employees often lie at the bottom of a long chain of supervisors, managers, and executives. Greater in height than the average person, building, etc. ; Having a specified height

Greater in height than the average person, building, etc. ; Having a specified height