noun
A casual outdoor meal, often in a park or scenic spot. The most common modern meaning.
週末に公園でピクニックをした。
We had a picnic in the park on the weekend.
Dated usage for a short excursion or hike, not necessarily involving a meal. Modern Japanese prefers 遠足 or ハイキング for this meaning.
昔は、山へのピクニックが流行っていた。
In the past, picnics to the mountains were popular.