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Second

The second is the SI base unit of time, symbol s. It defines a duration that is convenient for science and everyday life and provides the standard by which clocks, experiments, and communication systems are synchronized worldwide.

Historically, the second was once defined as 1/86400 of a mean solar day. Since 1967 it has

A minute equals 60 seconds and an hour equals 3,600 seconds. The second is used for timing

As an ordinal, second denotes the position following the first. The term, from Latin secundus via Old

In music, a second is the interval between two adjacent pitches (major or minor). In geometry, an

been
defined
by
the
frequency
of
radiation
from
the
cesium-133
atom:
9,192,631,770
periods
corresponding
to
the
transition
between
two
hyperfine
states.
across
laboratories,
manufacturing,
navigation,
and
sports,
and
is
the
basis
for
timekeeping
systems
such
as
Coordinated
Universal
Time
(UTC).
French,
also
appears
in
phrases
such
as
second-in-command,
second-best,
and
second-place.
arcsecond
is
1/3600
of
a
degree.
Colloquially,
"in
a
second"
means
very
soon.