gnomon

• POS: Noun
• HYPHEN: gno=mon

CIDE DICTIONARY

gnomon, n. [L. gnomon, Gr. one that knows, the index of a sundial. See Gnome.].

•  The style or pin, which by its shadow, shows the hour of the day. It is usually set parallel to the earth's axis.  [1913 Webster]
•  A style or column erected perpendicularly to the horizon, formerly used in astronomocal observations. Its principal use was to find the altitude of the sun by measuring the length of its shadow.  [1913 Webster]
•  The space included between the boundary lines of two similar parallelograms, the one within the other, with an angle in common; as, the gnomon bcdefg of the parallelograms ac and af. The parallelogram bf is the complement of the parallelogram df.  [1913 Webster]
•  The index of the hour circle of a globe.

OXFORD DICTIONARY

gnomon, n.
1 the rod or pin etc. on a sundial that shows the time by the position of its shadow.
2 Geom. the part of a parallelogram left when a similar parallelogram has been taken from its corner.
3 Astron. a column etc. used in observing the sun's meridian altitude.

Derivative

gnomonic adj.

Etymology

F or L gnomon f. Gk gnomon indicator etc. f. gignosko know

ROGET THESAURUS

gnomon

Chronometry

N chronometry, horometry, horology, date, epoch, style, era, almanac, calendar, ephemeris, register, registry, chronicle, annals, journal, diary, chronogram, clock, wall clock, pendulum clock, grandfather's clock, cuckoo clock, alarm clock, clock radio, watch, wristwatch, pocket watch, stopwatch, Swiss watch, atomic clock, digital clock, analog clock, quartz watch, water clock, chronometer, chronoscope, chronograph, repeater, timekeeper, timepiece, dial, sundial, gnomon, horologe, pendulum, hourglass, clepsydra, ghurry, chronographer, chronologer, chronologist, timekeeper, annalist, calendar year, leap year, Julian calendar, Gregorian calendar, Chinese calendar, Jewish calendar, perpetual calendar, Farmer's almanac, fiscal year, chronological, chronometrical, chronogrammatical, cinquecento, quattrocento, trecento, o'clock.