word formed from the first letters of a series of words, 1943, American English coinage from acro- + -onym "name" (abstracted from homonym; ultimately from PIE root *no-men- "name"). With the exception of cabalistic esoterica and acrostic poetry, this way of forming words was exceedingly uncommon before 20c. For distinction of usage (regretfully ignored on this site), see initialism.
The distinction from acronym is not universally agreed-upon; but in general, cases such as NATO, where the letters always are sounded as a word, are regarded as acronyms, those such as FBI, where the letters sound as letters, are initial-words or initialisms. The use of acronym in entries in this dictionary that are technically initialisms is a deliberate error, because many people will search all such words using "acronym."
Proto-Indo-European root meaning "name."
It forms all or part of: acronym; allonym; ananym; anonymous; antonomasia; antonym; binomial; caconym; cognomen; denominate; eponym; eponymous; heteronym; homonym; homonymous; hyponymy; ignominious; ignominy; innominable; Jerome; matronymic; metonymy; metronymic; misnomer; moniker; name; nomenclature; nominal; nominate; noun; onomastic; onomatopoeia; paronomasia; paronym; patronym; patronymic; praenomen; pronoun; pseudonym; renown; synonym; synonymy; synonymous; toponym.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit nama; Avestan nama; Greek onoma, onyma; Latin nomen; Old Church Slavonic ime, genitive imene; Russian imya; Old Irish ainm; Old Welsh anu "name;" Old English nama, noma, Old High German namo, Old Norse nafn, Gothic namo "name."
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."