To take (someone or something) part of the way you are going.
I don’t mind dropping you off at the store on my way to work.
Joe asked Mrs. Jones to drop him off at the library on her way downtown.
To become less. When the quality, degree, or frequency of something decreases, it falls off.
Business has been dropping off rapidly recently, but fortunately it hasn’t been falling off as quickly as for our competitors.
Business picked up in the stores during December, but dropped off again after Christmas.
Sales of fountain pens fell off after the ballpoint pen was invented.
The quality of his work has fallen off as he has gotten older.