The word "grasp" has several meanings, depending on its context.
1) To understand or comprehend something fully; to grasp a concept means to comprehend it completely. For example, "I'm having trouble grasping this new math concept."
2) To seize or take hold of something firmly; to grasp an object is to hold onto it tightly. Example: "She grasps the book tightly in her hands."
3) To have a good understanding or knowledge about something; to be well-versed in something means that you can explain and use it effectively. For example, "He has a good grasp of computer programming languages."
4) In a figurative sense, to seize an opportunity is also known as "grasping the nettle" - meaning taking decisive action despite potential risks or discomfort. Example: "We need to grasp the opportunities presented by this new market."