1660s, "first, earliest, existing from the beginning," especially in reference to inhabitants of lands colonized by Europeans, from aborigines (see aborigine) + -al (1). The specific Australian sense is attested from 1820, with capital A-. The noun meaning "an original inhabitant, an autochthon" is attested from 1760. Related: Aboriginally; aboriginality (1848); aboriginalism (1859).

type of tall herb or shrub native to the Mediterranean regions, 1660s, from Latin acanthus, name of the plant, from Greek akanthos, from akē "point, thorn" (from PIE root *ak- "be sharp, rise (out) to a point, pierce") + anthos "flower" (see anther). So called for its large spiny leaves. A conventionalized form of the leaf is used in Corinthian capitals. Related: Acanthaceous.

1660s, from Late Latin acceptabilitas, from Latin acceptabilis "worthy of acceptance," from acceptare "take or receive willingly" (see accept). Acceptableness (1610s) is older.

"state of being extremely precise or exact; conformity to truth," 1660s, from accurate + abstract noun suffix -cy.

"elevated part of a Greek city," often the site of original settlement and usually a citadel, 1660s, from Latinized form of Greek akropolis "citadel" (especially, with capital A-, that of Athens), from akros "highest, upper" (from PIE root *ak- "be sharp, rise (out) to a point, pierce") + polis "city" (see polis). The plural would be acropoles.

"quality that renders adaptable," 1660s, from adapt + -ability. In modern use especially in evolutionary biology, "variability in respect to, or under the influence of, external conditions."

"an expert, one who has attained knowledge," especially "one who is skilled in the secrets of an occult science," 1660s, from Latin adeptus (adj.) "having attained" (see adept (adj.)). The Latin adjective was used as a noun in this sense in Medieval Latin among alchemists. It implies natural and acquired ability, whereas expert implies more of experience and practice.

"sticky, cleaving or clinging," 1660s, from French adhésif, formed in French from Latin adhaes-, past-participle stem of adhaerere "stick to" (see adherent (adj.)).

"to make a pretense of," 1660s, earlier "to assume the character of (someone)," 1590s; originally in English in a now-obsolete sense of "aim at, aspire to, desire" (early 15c.), from Old French afecter (15c.), later affecter, from Latin affectare "to strive after, aim at, aspire to," frequentative of afficere (past participle affectus) "to do something to, act on, influence" (see affect (n.)). Related: Affected; affecting.

"miraculous communication of supernatural knowledge or power," 1660s, from Latin afflatus "a breathing upon, blast," figuratively "inspiration," noun use of past participle of afflare "to blow upon," from ad "to" (see ad-) + flare "to blow" (according to Watkins from PIE root *bhle- "to blow"). The literal meaning "a blowing or breathing upon" is rare in English, this sense being taken by afflation.