Gen`er*a"tion (?), n. [OE.
generacioun, F. génération, fr.L.
generatio.] 1. The act of generating or
begetting; procreation, as of animals.
2. Origination by some process, mathematical,
chemical, or vital; production; formation; as, the generation
of sounds, of gases, of curves, etc.
3. That which is generated or brought forth;
4. A single step or stage in the succession
of natural descent; a rank or remove in genealogy. Hence: The body of
those who are of the same genealogical rank or remove from an
ancestor; the mass of beings living at one period; also, the average
lifetime of man, or the ordinary period of time at which one rank
follows another, or father is succeeded by child, usually assumed to
be one third of a century; an age.
This is the book of the generations of
Adam. Gen. v. 1.
Ye shall remain there [in Babylon] many years, and for
a long season, namely, seven generations.
Baruch vi. 3.
All generations and ages of the Christian
5. Race; kind; family; breed;
Thy mother's of my generation; what's she, if I
be a dog? Shak.
6. (Geom.) The formation or production
of any geometrical magnitude, as a line, a surface, a solid, by the
motion, in accordance with a mathematical law, of a point or a
magnitude; as, the generation of a line or curve by the motion
of a point, of a surface by a line, a sphere by a semicircle,
7. (Biol.) The aggregate of the
functions and phenomene which attend reproduction.
☞ There are four modes of generation in the animal kingdom:
scissiparity or by fissiparous generation, gemmiparity
or by budding, germiparity or by germs, and oviparity
or by ova.
Alternate generation (Biol.),
alternation of sexual with asexual generation, in which the
products of one process differ from those of the other, -- a form of
reproduction common both to animal and vegetable organisms. In the
simplest form, the organism arising from sexual generation produces
offspiring unlike itself, agamogenetically. These, however, in time
acquire reproductive organs, and from their impregnated germs the
original parent form is reproduced. In more complicated cases, the
first series of organisms produced agamogenetically may give rise to
others by a like process, and these in turn to still other
generations. Ultimately, however, a generation is formed which
develops sexual organs, and the original form is reproduced. --
Spontaneous generation (Biol.), the
fancied production of living organisms without previously existing
parents from inorganic matter, or from decomposing organic matter, a
notion which at one time had many supporters; abiogenesis.