Gear set, movement, and timepiece

A gear set comprising:

• a first gear;
• and a second gear, wherein
• each tooth of the first gear includes
• a rigid tooth including a first acting tooth face that transmits motion to the second gear or to which motion from the second gear is transmitted and
• an elastic tooth provided away from the rigid tooth via a slit, configured to bend in a direction toward the rigid tooth when the elastic tooth meshes with the second gear, and including a first non-acting tooth face that contacts the second gear,
• a tooth thickness of each tooth of the first gear, the tooth thickness being a sum of a thickness of the rigid tooth, a width dimension of the slit, and a thickness of the elastic tooth of the first gear on a pitch circle of the first gear in a free state in which the first gear does not mesh with the second gear, is equal to or larger than a width of a tooth groove of the second gear on a pitch circle of the second gear, and
• a width of a tooth groove of the first gear on the pitch circle of the first gear is equal to or less than a tooth thickness of each tooth of the second gear on the pitch circle of the second gear.