Select the most appropriate one-word substitution for the given group of words. 

An instrument which records short intervals of time 

Chronograph

The most appropriate one-word substitution for "an instrument which records short intervals of time" is chronograph.

• Chronograph is a device that measures and displays short intervals of time.
• Seismograph is an instrument that measures and records earthquakes.
• Watch is a device that tells time.
• Calligraphy is the art of writing in a beautiful and elegant way.

The word chronograph comes from the Greek words "chronos," meaning "time," and "graphein," meaning "to write." A chronograph is typically used to measure short intervals of time, such as the time it takes to complete a race or the time it takes a heart beat. Chronographs can be very accurate and are often used in scientific research.