The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency, Δν Cs, the unperturbed ground-state hyperfine transition frequency of the …

The meaning of SECOND is next to the first in place or time. How to use second in a sentence.

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

next after the first; being the ordinal number for two. being the latter of two equal parts. the second house from the corner. the second person in the company. I have my hair cut every second …

second, fundamental unit of time, now defined in terms of the radiation frequency at which atoms of the element cesium change from one state to another. The second was formerly defined as …

A light flashing once per second. The second (symbol: s), is a unit of time. There are 60 seconds in a minute, 60 minutes in an hour, and 24 hours in a day. This tradition dates back to the …

2023年11月20日 · There are 24 hours in a day, 60 minutes in an hour, and 60 seconds in a minute — so surely a second is just 1/(24 x 60 x 60), or 1/86400, of a day, right? Well, it turns …

Define second. second synonyms, second pronunciation, second translation, English dictionary definition of second. n. 1. a. A unit of time equal to one sixtieth of a minute. b. The time …

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 …

SECOND definition: 1. referring to the person, thing, or event that comes immediately after the first: 2. 2nd written…. Learn more.