sec·ond¹ / ˈsekənd/ • ordinal number 1. constituting number two in a sequence; coming after the first in time or order; 2nd: he married for a second time Herbie was the second of their six children. ∎  secondly (used to introduce a second point or reason): second, they are lightly regulated; and third, they do business with nonresident clients. ∎  alternating; other: auctions are held every second week. ∎  Mus. an interval spanning two consecutive notes in a diatonic scale. ∎  the note that is higher by this interval than the tonic of a diatonic scale or root of a chord. ∎  the second in a sequence of a vehicle's gears: he took the corner in second. ∎ Baseball second base. ∎  the second grade of a school. ∎  (seconds) inf. a second course or second helping of food at a meal. ∎  denoting someone or something regarded as comparable to or reminiscent of a better-known predecessor: a fear that the conflict would turn into a second Vietnam. ∎  an act or instance of seconding.2. subordinate or inferior in position, rank, or importance: it was second only to Copenhagen among Baltic ports he is a writer first and a scientist second. ∎  additional to that already existing, used, or possessed: a second home French as a second language. ∎  the second finisher or position in a race or competition: he finished second. ∎ Brit. a place in the second-highest grade in an examination, esp. for a degree: she got a first in moral sciences and a second in history. ∎  Mus. performing a lower or subordinate of two or more parts for the same instrument or voice: the second violins. ∎  (seconds) goods of an inferior quality. ∎  coarse flour, or bread made from it.3. an assistant, in particular: ∎  an attendant assisting a combatant in a duel or boxing match.• v. [tr.] formally support or endorse (a nomination or resolution or its proposer) as a necessary preliminary to adoption or further discussion: Bertonazzi seconded Birmingham's nomination. ∎  express agreement with: her view is seconded by most Indian leaders today. ∎ archaic support; back up: so well was he seconded by the multitude of laborers at his command.PHRASES: in the second place as a second consideration or point.second to none the best, worst, fastest, etc.DERIVATIVES: sec·ond·er n.sec·ond² / ˈsekənd/ • n. 1. (abbr.: s) a sixtieth of a minute of time, which as the SI unit of time is defined in terms of the natural periodicity of the radiation of a cesium-133 atom. (Symbol: ″) ∎ inf. a very short time: his eyes met Charlotte's for a second.2. (also arc second or second of arc) a sixtieth of a minute of angular distance. (Symbol: ″) sec·ond³ / siˈkänd/ • v. [tr.] Brit. transfer (a military officer or other official or worker) temporarily to other employment or another position: I was seconded to a public relations unit.DERIVATIVES: sec·ond·ee / ˌsekənˈdē/ n.

second the ordinal number constituting number two in a sequence, coming after the first in time or order. The word comes (in Middle English, via Old French) from Latin secundus ‘following, second’, from the base of sequi ‘follow’.
it's the second mouse that gets the cheese modern extension of the early bird catches the worm, suggesting the dangers of being the first to make a venture, and the possible benefits of following directly behind a pioneer.
second Adam in Christian thought, Jesus Christ, with reference to 1 Corinthians 15:45; the actual phrase second Adam is first recorded in a marginal gloss on this passage from the Geneva Bible (1587).
second bite at the cherry another attempt or opportunity to do something; a cherry as the type of something to be consumed in a single bite (in original proverbial use, to take two bites at the cherry indicated a person's behaving with affected nicety).
Second Coming (also known as the Second Advent) the prophesied return of Christ to Earth at the Last Judgement; the term itself is recorded from the late 16th century.
Second Empire the imperial government in France of Napoleon III, 1852–70. The Second Republic was the republican regime in France from the deposition of King Louis Philippe (1848) to the beginning of the Second Empire (1852).
second sight the supposed ability to perceive future or distant events; clairvoyance. Reports of the faculty (recorded from the early 17th century) have traditionally been much associated with those of Scottish ancestry.
Second World the former communist block consisting of the Soviet Union and some countries in eastern Europe.
Second World War a war (1939–45) in which the Axis Powers (Germany, Italy, and Japan) were defeated by an alliance eventually including the United Kingdom and its dominions, the Soviet Union, and the United States.

See also second banana, second cousin, play second fiddle, have a second string to one's bow.

second1 coming next after the first XIII; next in rank or succession (e.g. s. lieutenant) XIV; from XVI in various techn. (mainly ellipt.) uses as sb. — (O)F. second, fem. -onde — L. secundus following, favourable, second, f. base of sequī follow.
So second sb. 1/60 of a minute. XIV. — (O)F. seconde — medL. secunda, sb. use of fem. of secundus, secunda minuta ‘second minute’ being the result of the second operation of sexagesimal division. secondary belonging to the second class or order XIV; also sb. XV. — L. secundārius; hence secondarily XV.

second (symbol s) SI unit of time defined as the time taken for 9,192,631,770 periods of vibrations of the electromagnetic radiation emitted by a caesium-133 atom. It is commonly defined as ¹/₆₀ of a minute. See also physical units

second.
1. As noun: interval in melody or harmony, being 2 steps in major or minor scale. Minor second is a semitone, e.g. C up to D♭; major second is 2 semitones, e.g. C up to D; augmented second is 3 semitones, e.g. C up to D♯.

2. As adjective: term denoting perf. of lower-pitched part, such as 2nd vn., 2nd tb.