The second (symbol: s) is a unit of time derived from the division of the day, first into hours, then into minutes, and lastly into seconds, for a total of 24 × 60 × 60 = 86 400 seconds per day. That definition, based on 1⁄86400 of a rotation of the Earth, is still used by the Universal Time 1 (UT1) system.

SECOND meaning: 1. immediately after the first and before any others: 2. the position in which a person finishes a…. Learn more.

1. In the second order, place, or rank: finished second. 2. But for one other; save one: the second highest peak.

A second may be one-sixtieth of a minute or the item after first. If you ask whether you're second in line, the hostess might reply, "Give me a second and I'll tell you." Different meanings of the word second have evolved from the same background, which is the Latin word secundus, which means "next" or "following."

Second The term "second" has a number of different meanings in the context of math and numbers. Possibly the most important is that it is the base unit of time in the International System of Units (SI). Other measurements of time, such as minutes, hours, days, weeks, and so on, are defined based on the second.

Learn about seconds, the fundamental unit of time measurement, including its scientific definition using Cesium-133 atoms, and explore practical time conversions between seconds, minutes, and hours through step-by-step examples and calculations.