9-letter words starting with a
- acetylide — any of a class of carbides in which the carbon is present as a diatomic divalent ion (C22–). They are formally derivatives of acetylene
- acetyloxy — (organic chemistry, especially in combination) The radical CH3COO-, common to acetate esters, when used as a substituent.
- achalasia — failure of the cardiac sphincter of the oesophagus to relax, resulting in difficulty in swallowing
- acheilary — having no labellum or lip, or one that is undeveloped, as in the flower of certain orchids.
- acheulean — designating or of a Lower Paleolithic culture characterized by skillfully made bifacial flint hand axes
- acheulian — (in Europe) the period in the Lower Palaeolithic following the Abbevillian, represented by the use of soft hammerstones in hand axe production made of chipped stone, bone, antler, or wood. The Acheulian dates from the Riss glaciation
- achievers — to bring to a successful end; carry through; accomplish: The police crackdown on speeders achieved its purpose.
- achieving — to bring to a successful end; carry through; accomplish: The police crackdown on speeders achieved its purpose.
- achillean — the greatest Greek warrior in the Trojan War and hero of Homer's Iliad. He killed Hector and was killed when Paris wounded him in the heel, his one vulnerable spot, with an arrow.
- achimenes — any plant of the tropical S American tuberous-rooted perennial genus Achimenes, with showy red, blue, or white tubular flowers, some of which are grown as greenhouse plants: family Gesneriaceae
- acholuria — the absence of bile pigments in the urine.
- achromate — a person unable to perceive color.
- achromats — Plural form of achromat.
- achromous — Colorless; achromatic.
- aciculate — having aciculae
- acid cell — Electricity. a cell using an acid electrolyte.
- acid drop — a boiled sweet with a sharp taste
- acid dust — air-polluting particles of dust, usually wind-borne, having high concentrations of acid.
- acid jazz — a type of music, popular in the 1980s and 1990s, that combines jazz with genres such as funk, hip-hop, and electronic dance music
- acid rain — Acid rain is rain polluted by acid that has been released into the atmosphere from factories and other industrial processes. Acid rain is harmful to the environment.
- acid rock — a type of rock music characterized by electronically amplified bizarre instrumental effects
- acid salt — a salt formed by partial replacement of the acidic hydrogen atoms of the parent acid
- acid soil — a soil that gives a pH reaction of below about 6, found esp in cool moist areas where soluble bases are leached away
- acid test — The acid test of something is an important aspect or result that it might have, which allows you to decide whether it is true or successful.
- acid trip — a psychedelic experience induced by ingesting the hallucinogen LSD.
- acid-fast — (of bacteria and tissues) resistant to decolorization by mineral acids after staining
- acid-head — a person who habitually takes the drug LSD.
- acidaemia — (medicine) a medical condition marked by an abnormally high concentration of hydrogen ions in a person's blood.
- acidaemic — Pertaining to, or afflicted with, acidaemia.
- acidified — Simple past tense and past participle of acidify.
- acidifies — Third-person singular simple present indicative form of acidify.
- acidities — Plural form of acidity.
- acidizing — Acidizing is the injection of acid into the reservoir rock to enlarge the pore spaces and increase the flow of oil.
- acidophil — (of cells or cell contents) easily stained by acid dyes
- acidulant — an acidulating substance.
- acidulate — to make slightly acid or sour
- acidulent — an acidulating substance.
- acidulous — rather sour
- aciniform — shaped like a bunch of grapes
- acnegenic — causing or able to cause acne.
- acoluthic — following, subsequent; specifically, relating to an afterimage
- aconcagua — a mountain in W Argentina: the highest peak in the Andes and in the W Hemisphere. Height: 6960 m (22 835 ft)
- aconitine — a poison extracted from aconite
- acorn cup — the woody cuplike base that holds the nut from an oak tree
- acoustics — the scientific study of sound and sound waves
- acquaints — Third-person singular simple present indicative form of acquaint.
- acquiesce — If you acquiesce in something, you agree to do what someone wants or to accept what they do.
- acquirers — Plural form of acquirer.
- acquireth — Archaic third-person singular form of acquire.
- acquiring — to come into possession or ownership of; get as one's own: to acquire property.