The terminology or language could not be changed easily.The terminology or language can not be changed as you like to change the language and terminology is a matter of people, so the terminology has been changed to be accepted by most people.
Vocabulary or language can not be changed easily. vocabulary or language does not change as you change the words and language is of the people, so the terminology is changed, it must be accepted by most people.
Vocabulary or language cannot be changed easily .Vocabulary or language cannot be changed like changes in vocabulary and language is a most of people so vocabulary changes will have to be accepted by most people.