Etymology
Advertisement
acer (n.)
maple tree genus, from Latin acer, of uncertain origin, perhaps from PIE *ak- "be sharp" (see acro-) and so called for its pointed leaves. There seem to have been two roots for "maple" in Indo-European; cognates of this one are said to include Old High German ahorn "maple," and there is a similar form in Greek akastos "maple," perhaps also Hittite hiqqar- "maple." De Vaan writes, "This may well be a non-PIE tree name which was borrowed into Greek and Latin."
Related entries & more 
Advertisement
*ak- 
Proto-Indo-European root meaning "be sharp, rise (out) to a point, pierce."

It forms all or part of: acacia; acanthus; accipiter; acer; acerbic; acerbity; acervate; acervulus; acescent; acetic; acid; acicular; acme; acne; acrid; acridity; acrimony; acro-; acrobat; acromegaly; acronym; acrophobia; acropolis; acrostic; acrylic; acuity; aculeate; acumen; acupressure; acupuncture; acute; aglet; ague; Akron; anoxic; awn; coelacanth; dioxin; deoxy-; eager; ear (n.2) "grain part of corn;" edge (n.); egg (v.) "to goad on, incite;" eglantine; epoxy; ester; exacerbation; hammer; hypoxia; mediocre; oxalic; oxide; oxy-; oxygen; oxymoron; paragon; pyracanth; paroxysm; selvage; vinegar.

It is the hypothetical source of/evidence for its existence is provided by: Greek akros "at the end, at the top, outermost; consummate, excellent," akis "sharp point," akros "at the farthest point, highest, outermost," akantha "thorn," akme "summit, edge," oxys "sharp, bitter;" Sanskrit acri- "corner, edge," acani- "point of an arrow," asrih "edge;" Oscan akrid (ablative singular) "sharply;" Latin acer (fem. acris) "sharp to the senses, pungent, bitter, eager, fierce," acutus "sharp, pointed," acuere "to sharpen," acerbus "harsh, bitter," acere "be sharp, be bitter," acus "a needle, pin," ocris "jagged mountain;" Lithuanian ašmuo "sharpness," akstis "sharp stick;" Old Lithuanian aštras, Lithuanian aštrus "sharp;" Old Church Slavonic ostru, Russian óstryj "sharp;" Old Irish er "high;" Welsh ochr "edge, corner, border;" Old Norse eggja "goad;" Old English ecg "sword;" German Eck "corner."
Related entries & more 
acescent (adj.)

"becoming sour," 1670s, from French acescent, from Latin acescentem (nominative acescens), present participle of acescere "become sour," from acer "sharp" (from PIE root *ak- "be sharp, rise (out) to a point, pierce").

Related entries & more 
acervulus (n.)

"brain-sand" (anatomical), 1806, medical Latin, literally "little heap," diminutive of Latin acervus "heap," which is akin to acer "sharp" (from PIE root *ak- "be sharp, rise (out) to a point, pierce").

Related entries & more 
acervate (v.)

"to heap up," 1610s, from Latin acervatus, past participle of acervare "to heap up," from acervus "heap," which is akin to acer "sharp," from PIE root *ak- "be sharp, rise (out) to a point, pierce." Related: Acervated; acervating; acerval; acervative; acervuline "occurring in clusters; clustered" (by 1859).

Related entries & more 
Advertisement
acetic (adj.)
1808 (in acetic acid), from French acétique "pertaining to vinegar, sour, having the properties of vinegar," from Latin acetum "vinegar" (properly vinum acetum "wine turned sour;" see vinegar), originally past participle of acere "be sharp; be sour" (related to acer "sharp"), from PIE *ak-eto-, suffixed form of root *ak- "be sharp, rise (out) to a point, pierce."
Related entries & more 
acrimony (n.)

1540s, "quality of being sharp or pungent in taste," from French acrimonie or directly from Latin acrimonia "sharpness, pungency of taste," figuratively "acrimony, severity, energy," abstract noun from acer "sharp" (fem. acris), from PIE root *ak- "be sharp, rise (out) to a point, pierce") + -monia suffix of action, state, condition. Figurative extension to personal sharpness or bitterness is by 1610s.

Related entries & more 
acerbity (n.)
Origin and meaning of acerbity

1570s, from French acerbité, from Latin acerbitatem (nominative acerbitas) "harshness, sharpness, bitterness, sourness," literal and figurative (as in virus acerbitatis "the poison of malice"), from acerbus "bitter to taste, sharp, sour, tart," from Proto-Italic *akro-po- "sharp" (from PIE root *ak- "be sharp, rise (out) to a point, pierce"). Earliest use in English is figurative, of "sharp and bitter" persons. Of tastes, from 1610s. Latin acerbus is related to acer "sharp" as superbus "haughty" to super "above."

Related entries & more 
exacerbation (n.)

"act of exacerbating; state of being exacerbated; increase of violence or virulence, aggravation," c. 1400, exacerbacioun, from Late Latin exacerbationem (nominative exacerbatio), noun of action from past-participle stem of Latin exacerbare "exasperate, irritate, provoke," from ex, here probably "thoroughly" (see ex-), + acerbus "harsh, bitter," from acer "sharp, keen," from PIE root *ak- "be sharp, rise (out) to a point, pierce." Oldest use in English is Biblical, in reference to the Provocation in the Wilderness.

Related entries & more 
acrylic (adj.)
1843, "of or containing acryl," the name of a radical derived from acrolein (1843), the name of a liquid in onions and garlic that makes eyes tear, from Latin acer "sharp" (from PIE root *ak- "be sharp, rise (out) to a point, pierce") + olere "to smell" (see odor) + -in (see -ine (2)). With adjectival suffix -ic. Modern senses often short for acrylic fiber, acrylic resin, etc.
Related entries & more