The saying is "in terms of". You use "in terms of" when you want to focus the subject of what you're going to say:
"In terms of the car, it was not damaged."
"In terms of Mr. Smith, his work is very good."
There are other usages, of course, but those are the most basic.
"You can understand english in terms of the meaning of the words I'm speaking".
However, not many english speakers use "in terms of" anymore. Normally people would say:
"The car was damaged"
"Mr. Smith's work is very good"
"By understanding the meanings of the words I speak, you can understand english."