One-Handed Path of Exile 2 game term
One-handed weapons can be placed in the main weapon slot. Some one-handed weapon types can be dual wielded in both main and off hand weapon slots.
The game's own definition, as shown when you hover the term in game.
Game data: Path of Exile 2 client · How we source this
One-handed weapons can be placed in the main weapon slot. Some one-handed weapon types can be dual wielded in both main and off hand weapon slots.