cookout
n.an outdoor party where people cook and eat food together, usually on a grill. Common in American English.
n.a social gathering held outdoors at which food is cooked and eaten, typically over a charcoal or gas grill. Chiefly North American usage.
“We're having a cookout in the backyard tomorrow.”
“The neighbors organized a cookout for Memorial Day weekend, grilling burgers and hot dogs for everyone on the block.”
“What began as a modest family cookout gradually swelled into a street-wide celebration, with folding tables laden with potluck dishes stretching halfway down the cul-de-sac.”
From cook + out, a compound formed on the model of verbs taking directional particles — eat out, dine out — applied to the specific practice of preparing a meal outdoors.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.