freely; unrestrained; with full command
Describes moving, acting, or handling something with complete freedom and skill, as if one can go in any direction without hindrance. Often used for mastery of a skill or unrestricted activity.
He handles the computer with complete freedom and skill.
The player moved around the field freely and unrestrainedly.
自由自在 also means 'freely' or 'at will,' but 縦横自在 emphasizes the spatial or directional aspect of freedom, like moving in all directions or handling something with versatile mastery.
A yojijukugo combining 縦横 (vertical and horizontal, i.e., all directions) and 自在 (freely, at will). The exact historical origin is uncertain, but it follows a common pattern of four-character compounds expressing unrestricted movement or ability.