late 14c., "breadth," from Old French latitude (13c.) and directly from Latin latitudo "breadth, width, extent, size," from lātus (adj.) "wide, broad, extensive" Old Latin stlatus, from PIE *stleto-, suffixed form of root *stele- "to spread, to extend" (source also of Old Church Slavonic steljo "to spread out," Armenian lain "broad").
Geographical and astronomical senses also are from late 14c., literally "breadth" of a map of the known world. Figurative sense of "allowable degree of variation, extent of deviation from a standard" is early 15c. Related: Latitudinal "pertaining to geographic latitude" (1777); latitudinous "having broadness of interpretation" (1829, American English).
The ancients supposed the torrid and the frigid zones to be uninhabitable and even impenetrable by man, but while the earth, as known to them, was bounded westwardly by the Atlantic Ocean, it extended indefinitely towards the east. The dimensions of the habitable world then (and ancient geography embraced only the home of man ....,) were much greater, measured from west to east, than from south to north. Accordingly, early geographers called the greater dimension, or the east and west line, the length, longitudo, of the earth, the shorter dimension, or the north and south line, they denominated its breadth, latitudo. These Latin terms are retained in the modern geography of most European nations, but with a modified meaning. [George P. Marsh, "Lectures on the English Language," 1882]
late 14c., dilaten, "describe at length, speak at length," from Old French dilater and directly from Late Latin dilatare "make wider, enlarge," from dis- "apart" (see dis-) + lātus "broad, wide, widespread, extended" (see latitude). Meaning "expand, distend, spread out, enlarge in all directions" (transitive) is from early 15c.; intransitive sense of "spread out, expand, distend" also is from early 15c. A doublet of delay. Related: Dilated; dilating.
c. 1400, dilatacioun, "act of expanding, expansion," especially "abnormal enlargement of an aperture of the body," from Old French dilatation and directly from Late Latin dilatationem (nominative dilatatio) "a widening," noun of state from past-participle stem of Latin dilatare "make wider, enlarge," from dis- "apart" (see dis-) + lātus "broad, wide, widespread, extended" (see latitude). Also in Middle English "amplification in discourse" (late 14c.). In gynecology dilatation and curettage is by 1896.
"act of going before or moving forward, an advance," 1590s, from Late Latin praecissionem (nominative praecissio) "a coming before," from past-participle stem of Latin praecedere "to go before" (see precede). Originally used in reference to calculations of the equinoxes, which come slightly earlier each year, a phenomenon discovered by Hipparchus (190 B.C.E.-120 B.C.E.).
Alpha Centauri was still visible at the latitude of New York, B. C. 300. Ten thousand years ago its meridian altitude at the latitude of Washington was about 30 degrees. At that time Sirius did not appear above our horizon ; and it is interesting to observe that in our latitude these two magnificent stars can never be within the circle of perpetual occultation at the same time. The whole constellation of the Southern Cross was visible in Southern Europe until after the commencement of historic times. Its brightest star, however, will not reappear in the latitude of New York till about A. D. 20,000. [Prof. Daniel Kirkwood, "Changes in Celestial Scenery," in Our Monthly, July 1871]
The word is attested much older (early 14c.) as an error for procession. Related: Precessional.
1843 as the years of someone's life between 40 and 49; from 1840 as the fifth decade of years in a given century. See forty. Also a designation applied in various places and times to certain oligarchies, ruling classes, or governing bodies.
It is well known that society in the island [Guernsey] is, or perhaps we ought to say, for many years was, divided into two sets, called respectively the Sixties and the Forties, the former composed of the old families and those allied to them, the latter of families of newly-acquired wealth and position. [The Dublin Review, October 1877]
Roaring Forties are rough parts of the ocean between 40 and 50 degrees latitude.
1550s in astronomy, in reference to a celestial circle, a line around the sky which, in any location, bounds the stars which are ever-visible from that latitude (in the Northern Hemisphere its center point is the celestial north pole); the concept goes back to the ancient Greeks, for whom this set of constellations included most prominently the two bears (arktoi), hence the name for the circle (see arctic). In Middle English it was the north cercle (late 14c.).
In geography, from 1620s as "the circle roughly 66 degrees 32 minutes north of the equator" (based on obliquity of the ecliptic of 23 degrees 28 minutes), marking the southern extremity of the polar day, when the sun at least theoretically passes the north point without setting on at least one summer day and does not rise on at least one winter one.