pictogram n.

mid-13c., peinten, "represent (someone or something) in paint;" c. 1300, "decorate (something or someone) with drawings or pictures;" early 14c., "put color or stain on the surface of; coat or cover with a color or colors;" from Old French peintier "to paint," from peint, past participle of peindre "to paint," from Latin pingere "to paint, represent in a picture, stain; embroider, tattoo," from a nasalized form of PIE root *peig- "to cut, mark by incision."

The sense evolution between PIE and Latin was, presumably, "decorate with cut marks" to "decorate" to "decorate with color." Compare Sanskrit pingah "reddish," pesalah "adorned, decorated, lovely;" Old Church Slavonic pegu "variegated;" Greek poikilos "variegated;" Old High German fehjan "to adorn;" Old Church Slavonic pisati, Lithuanian piešiu, piešti "to write." Probably also representing the "cutting" branch of the family is Old English feol (see file (n.2)).

From late 14c. as "represent persons and things in pictures or drawing, portray." To paint the town (red) "go on a boisterous or disorderly spree" is by 1884; to paint (someone or something) black "represent it as wicked or evil" is from 1590s. Adjective paint-by-numbers "simple" is attested by 1970; the art-for-beginners kits themselves date to c. 1953.

noun word-forming element, "that which is written or marked," from Greek gramma "that which is drawn; a picture, a drawing; that which is written, a character, an alphabet letter, written letter, piece of writing;" in plural, "letters," also "papers, documents of any kind," also "learning," from stem of graphein "to draw or write" (see -graphy). Some words with it are from Greek compounds, others are modern formations. Alternative -gramme is a French form.

From telegram (1850s) the element was abstracted by 1959 in candygram, a proprietary name in U.S., and thereafter put to wide use as a second element in forming new commercial words, such as Gorillagram (1979), stripagram (1981), and, ultimately, Instagram (2010). The construction violates Greek grammar, as an adverb could not properly form part of a compound noun. An earlier instance was the World War II armed services slang latrinogram "latrine rumor, barracks gossip" (1944).

also *peik-, Proto-Indo-European root meaning "to cut, mark by incision," hence "embroider, paint."

It forms all or part of: depict; file (n.2) "metal tool for abrading or smoothing;" paint; pictogram; pictograph; pictorial; picture; picturesque; pigment; pimento; pint; pinto.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit pimsati "to carve, hew out, cut to measure, adorn;" Greek pikros "bitter, sharp, pointed, piercing, painful," poikilos "spotted, pied, various;" Latin pingere "to embroider, tattoo, paint, picture;" Old Church Slavonic pila "file, saw," pegu "variegated," pisati "to write;" Lithuanian piela "file," piešiu, piešti "to write;" Old High German fehjan "to adorn."