simple past tense and past participle of appreciate
"She appreciated his help when he carried her heavy bags to the car."
In plain English: To appreciate something means to realize how good it is and value what you have received from someone else.
"I really appreciated your help with moving today."
fully understood or grasped
"dangers not yet appreciated"
"these apprehended truths"
"a thing comprehended is a thing known as fully as it can be known"
recognized as having value
"The rare first edition was highly appreciated by collectors for its historical significance."
In plain English: Appreciated means someone values you and thinks your actions are important to them.
"The quiet atmosphere in the library was greatly appreciated by all the students studying there."