"Parm” is a shortened form of “parmigiana.” “Eggplant Parm.” has been cited in print since at least 1968. ‘Eggplant parm” (without the period) has been cited in print since at least 1975.
“Parm” has been popularized by Italian restaurants throughout the United States.
(Oxford English Dictionary)
Etymology: Shortened < either parmigiana adj. and n. or Parmesan n., originally as graphic abbreviation.
= PARMIGIANA n.
1974 Marion (Ohio) Star 10 Apr. 4/2 Sliced Turkey & Gravy, Beef Stew, Veal Parm., Chicken & Dumpling or Salisbury Steak.
1986 Smithsonian Nov. 102/2 Linda is chalking the dinner specials on the menu board: chopped steak $4.85, roast turkey $4.65, chicken parm $5.25.
1992 Atlantic Sept. 84/2, I have a VCR, and some eggplant parm in the fridge.
2000 N.Y. Press 29 Mar. i. 3/1 Eight dollars and 88 cents for a meal of coffee and chicken parm, location unspecified.
13 September 1968, Bucks County Courier Times (Levittown, PA), pg. 16, col. 3 ad:
EGGPLANT PARM. $1.35
(Joe Scarpati’s Woodbourne Tavern—ed.)
16 February 1972, The Evening Times (Trenton, NJ), pg. 8, col. 8 ad:
Side of Spag. or Eggplant Parm., Soup or Salad.
(Maruca’s Gas Light Pizza and Restaurant of Morrisville, PA—ed.)
12 January 1975, Sunday Times Advertiser (Trenton, NJ), pt. 3, pg. 15, col. 1 ad:
MEAT RAVIOLI PARM.
CHEESE RAVIOLI PARM.
69c 12-OZ. PKG.
(Grand Union’s Family Center—ed.)
25 January 1975, Independent Press-Telegram (Long Beach, CA), pg. B3, col. 3 photo caption:
His menu choices are varied, going from “eggplant parm” to Hero sandwiches to Virginia ham.
22 October 1979, Trenton (NJ) Times, pg. A2, col. 4 ad:
Zucchini Parm Sandwich
(Del Rio Restaurant & Cocktail Lounge—ed.)
19 November 1979,
HOT MEATBALL PARM. SANDWICH $1,70
The Huffington Post
The Best Eggplant Parm Sandwich Recipe
Posted: 08/16/2012 9:07 am Updated: 08/31/2012 10:48 am
It wouldn’t be a daily indulgence if we didn’t provide you with an over-the-top recipe (that we know you just can’t wait to try). Yesterday, it was a thousand-layer chocolate chip cookie, and today it’s a mile-high eggplant parm sandwich.