Popularized in England in children's literature from early 19c. as a name for red-capped German and Swiss folklore dwarfs. Garden figurines of them were first imported to England late 1860s from Germany; garden-gnome attested from 1933. Gnomes of Zurich for "international financiers" is from 1964.
"short, pithy statement of general truth," 1570s, from Greek gnōmē "judgment, opinion; maxim, the opinion of wise men," from PIE root *gno- "to know."
*gnō-, Proto-Indo-European root meaning "to know."
It forms all or part of: acknowledge; acquaint; agnostic; anagnorisis; astrognosy; can (v.1) "have power to, be able;" cognition; cognizance; con (n.2) "study;" connoisseur; could; couth; cunning; diagnosis; ennoble; gnome; (n.2) "short, pithy statement of general truth;" gnomic; gnomon; gnosis; gnostic; Gnostic; ignoble; ignorant; ignore; incognito; ken (n.1) "cognizance, intellectual view;" kenning; kith; know; knowledge; narrate; narration; nobility; noble; notice; notify; notion; notorious; physiognomy; prognosis; quaint; recognize; reconnaissance; reconnoiter; uncouth; Zend.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit jna- "know;" Avestan zainti- "knowledge," Old Persian xšnasatiy "he shall know;" Old Church Slavonic znati "recognizes," Russian znat "to know;" Latin gnoscere "get to know," nobilis "known, famous, noble;" Greek gignōskein "to know," gnōtos "known," gnōsis "knowledge, inquiry;" Old Irish gnath "known;" German kennen "to know," Gothic kannjan "to make known."
"full of instructive sayings," 1784, from French gnomique (18c.) and directly from Late Latin gnomicus "concerned with maxims, didactic," from Greek gnōmikos, from gnōmē "a means of knowing, a mark, token; the mind (as the organ of knowing), thought, judgment, intelligence; (one's) mind, will, purpose; a judgment, opinion; maxim, the opinion of wise men," from root of gignōskein "to come to know," from PIE root *gno- "to know." Gnomical is attested from 1610s.