achoppement (-shop-mān), n.m., stumbling, impediment. Pierre d’—; stumbling-block.

achopper, v.n., to stumble, to knock one’s self against anything; (fig.) to fail.

achromatique (-kro-), adj., achromatic.

achromatisme (-kro-), n.m., (opt.) achromatism.

achronique (-kro-), adj. V. acronyque.

aciculaire, adj., acicular, needle-shaped.

acide, n.m., acid.

acide, adj., acid, sour, tart, sharp.

acidifier, v.a., to acidify.

acidité, n.f., acidity, sourness, sharpness, tartness.