buttonwood (n.)

c. 1300, "knob or ball attached to another body," especially as used to hold together different parts of a garment by being passed through a slit or loop (surname Botouner "button-maker" attested from mid-13c.), from Old French boton "a button," originally "a bud" (12c., Modern French bouton), from bouter, boter "to thrust, strike, push," common Romanic (cognate with Spanish boton, Italian bottone), ultimately from a Germanic source, from Proto-Germanic *buttan, from PIE root *bhau- "to strike." Thus a button is, etymologically, something that pushes up, or thrusts out.

The meaning "point of the chin" is pugilistic slang, by 1921. A button as a round protuberance you depress to create an effect by closing an (electrical) circuit is attested from 1840s. Button-pusher as "deliberately annoying or provocative person" is attested by 1990 (in reference to Bill Gates, in "InfoWorld" magazine, Nov. 19). In the 1980s it meant "photographer."

Old English wudu, earlier widu "tree, trees collectively, forest, grove; the substance of which trees are made," from Proto-Germanic *widu- (source also of Old Norse viðr, Danish and Swedish ved "tree, wood," Old High German witu "wood"), from PIE *widhu- "tree, wood" (source also of Welsh gwydd "trees," Gaelic fiodh- "wood, timber," Old Irish fid "tree, wood"). Out of the woods "safe" is from 1792.

mid-14c., sicamour "mulberry-leaved fig tree," from Old French sicamor, sagremore, from Latin sycomorus, from Greek sykomoros "African fig-tree," literally "fig-mulberry," from sykon "fig" (see fig) + moron (see mulberry). But according to many sources this is more likely a folk-etymology of Hebrew shiqmah "mulberry."

A Biblical word, originally used for a wide-spreading shade tree with fig-like fruit (Ficus sycomorus) common in Egypt, Palestine, Syria, etc., whose leaves somewhat resemble those of the mulberry; applied in English from 1580s to a large species of European maple (also plane-tree), perhaps because both it and the Biblical tree were notable for their shadiness (the Holy Family took refuge under a sycamore on the flight to Egypt), and from 1814 to the North American shade tree that also is called a buttonwood, which was introduced to Europe from Virginia 1637 by John Tradescant the Younger).

Spelling apparently influenced by sycamine "black mulberry tree," which is from Greek sykcaminos, which also is mentioned in the Bible (Luke xvii.6). For the sake of clarity, some writers have used the more Hellenic sycomore in reference to the Biblical tree.