Coach has two main meanings that connect through the idea of guidance and movement:

1. A person who trains and instructs athletes or teams. A basketball coach teaches players techniques, designs plays, and helps the team work together effectively. Coaches also help individual athletes improve: a gymnastics coach might spend hours perfecting a student's form on the balance beam. Good coaches don't just know the sport, they know how to motivate people, spot weaknesses, and build confidence. The word can extend beyond sports: a debate coach helps students argue persuasively, while a vocal coach trains singers.
2. A large bus designed for long-distance travel, or historically, a horse-drawn carriage. Tour groups might travel by coach when visiting national parks. Before cars and trains existed, a stagecoach carried passengers and mail between towns, pulled by teams of horses that would be swapped out at stations along the route.

Both meanings share the idea of carrying someone toward a destination: a vehicle carries you physically, while a coach helps carry you toward your goals through teaching and encouragement.

As a verb, to coach means to train, guide, or prepare someone by giving instruction and feedback.