What is an antonym? How is it used to define a word or term? ...

[penza]

What is an antonym? How is it used to define a word or term?
 
  What will be an ideal response?

Question 2

What is a synonym? How is it used to define a word or term?
 
  What will be an ideal response?

[janieazgirl]

Answer to Question 1

An antonym is a word or term that has the opposite meaning as the word
or term being defined. An antonym is used to explain the meaning of a
word or term through a word or term that has the opposite meaning.

Answer to Question 2

A synonym is, generally, a familiar word or phrase that has the same
meaning as the unfamiliar word. A synonym is used to explain the
meaning of a word or term that may be unfamiliar to the reader through a
word or term that the reader probably knows.

[penza]

Excellent

[Laurenleakan]

Thanks for the timely response, appreciate it