Crossword Genius

Since, for short (3)

Ross

I believe the answer is:

est

(Other definitions for est that I've seen before include "self-improvement programme" , "psychological programme" , "Suffix showing superlative" , "Time Americans adopted" .)

I've seen this clue in the Newsday.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.