The difference between Grasp and Understand

When used as verbs, grasp means to grip, whereas understand means to be aware of the meaning of.

Grasp is also noun with the meaning: grip.

check bellow for the other definitions of Grasp and Understand

Grasp as a verb:

To grip; to take hold, particularly with the hand.
Grasp as a verb:

To understand.

Examples:

"I have never been able to grasp the concept of infinity."
Grasp as a verb:

To take advantage of something, to seize, to jump at a chance.

Grasp as a noun (sometimes, figurative):

Grip.
Grasp as a noun:

Understanding.
Grasp as a noun:

That which is accessible; that which is within one's reach or ability.

Examples:

"The goal is within my grasp."

Understand as a verb (transitive):

To be aware of the meaning of.

Examples:

"I understand German."

"I received your note, but I did not understand it."
Understand as a verb:

To believe, based on information.

Examples:

"I understand that you have information for me."
Understand as a verb:

To impute meaning, character etc. that is not explicitly stated.

Examples:

"But we cannot disappoint Grandma and Grandpa Smith, and that is what family is all about! Do you understand?!"

"In this sense, the word is usually used in the past participle:"
Understand as a verb (obsolete, rare, humorous):

To stand under; to support.

Examples:

"rfquotek Shakespeare"
Understand as a verb (circus, acrobatics):

One who supports others in such performances as the human pyramid.