A daypack is a small bag for one day's walking. Carry a daypack.
Twenty to thirty litres is the usual size, which holds food, water and a coat. A daypack with a hip belt carries far better than one without, even when it is light.
1noundaypackA small bag for one day's walking.
“The daypack held lunch, a map and two spare pairs of socks.”
daypack is a bag.
Day plus pack, from American hiking usage.
From day + pack.
Etymology from Wiktionary, CC BY-SA
Practised in Camping & Outdoors