The language around the lanes.

Nineteen useful terms for following a meet, reading a result or asking a clearer question.

Course: The pool configuration used for a swim. Keep its length and units with recorded times.
Event: A scheduled race category identified by details such as distance, stroke and participant category.
Heat: One group racing within an event. An event can have several heats.
Heat sheet: The document listing race assignments such as event, heat and lane. It is not the same as final results.
Individual medley (IM): A race in which one swimmer completes butterfly, backstroke, breaststroke and freestyle, in that order under USA Swimming rules.
Lane: The marked swimming position assigned within a heat or used within a practice arrangement.
LCM: Long-course meters: a 50-meter pool course. Keep this label with times recorded on that course.
Length: A single trip from one end of the pool to the other. Use this precise word when “lap” might be ambiguous.
Medley relay: A relay using backstroke, breaststroke, butterfly and freestyle in that order under USA Swimming rules, with different swimmers completing the legs.
Pace: A time expressed for a stated distance, such as minutes and seconds per 100 meters. An average does not show every variation during a swim.
Personal best: An athlete’s fastest recorded performance for a specified event and course within the relevant record context.
Platform: A fixed takeoff surface used in diving. Participation requires suitable facilities and qualified supervision.
Relay: A team race divided into legs completed by different swimmers according to the event’s rules.
SCM: Short-course meters: a 25-meter pool course.
SCY: Short-course yards: a 25-yard pool course. Yards and meters are different units.
Seed time: The entry time used in arranging a race. It is not the result of the race about to happen.
Split: A time associated with a portion of a swim. Check whether a report shows interval splits or cumulative elapsed times.
Springboard: A flexible board used as a takeoff surface in diving; it differs from a fixed platform.
Warm-up: Preparation before a session or event. Follow the coach’s and facility’s instructions for the actual activity.

These are plain-language explanations. For competition decisions, use the current governing rules and the meet’s official information. For diving terminology, consult USA Diving’s glossary.