酔い止め

1. Origins, structure, and basic meaning

• Structure: 酔い止め, read よいどめ, combines motion sickness 酔い with prevention 止め as a medicine-use name.
• Basic usage: It denotes medicine used to prevent or reduce motion sickness, as in 船に乗る前に酔い止めを用意する.

2. Common pitfalls and similar expressions

• Scope and context
  • It is for motion sickness 乗り物酔い, not medicine that prevents intoxication from alcohol.