natch /nætʃ/, adv. Colloq. abbrev. of naturally adv. orig. U.S.
1945 in L. Shelly Jive Talk Dict. 15/1.
1946 Sun (Baltimore) 24 Sept. 3/3 (Advt.), ― Natch! Mom’s gettin’ both of us Hen self-starters··. Baltimore’s most popular ‘first shoes for babies’.
1953 New Yorker 10 Jan. 21/3 ― Their disapproving papa··inserted a dime, which, he said, would otherwise have gone to buy them a Coca-Cola··. Well, natch, this brought a twenty-dime return.
1957 P. Wildeblood Main Chance 132 ― ‘You don’t mean to say,’ she whispered tragically, ‘that we’re going to eat?’ ‘Why, natch. We’re going to have anoth…