Understand (verb)

1. To grasp the meaning of (something spoken or written).
2. To perceive the intended meaning of.

Origin:

Middle english understanden, from old english understandan; akin to old high german untarstāzan to stand under, latin sub- under + tendere to stretch.

Examples:

1. I understand what you're saying.
2. He didn't understand the instructions.
3. She understood the implications of her actions.
4. I understand that you are busy.
5. He understood the joke and laughed.