natch
slang A shortening of the word "naturally," meaning "of course." The spelling approximates the sound of the first syllable of "naturally." Primarily heard in US. A: "And did you adjust for inflation?" B: "Natch! The numbers all check out, man." A: "Is it all right if I borrow your computer for a while?" B: "Natch, dude. No problem."
on the natch
slang No longer using or addicted to drugs or alcohol; in a clean, natural state. ("Natch" is a slang shortening of "natural.") My wife and parents helped me get through rehab five years ago, and I've been on the natch ever since.