The property of radiant energy (found chiefly in solar or electric light) by which chemical changes are produced, as in photography.

A supposed metal, said by Phipson to be contained in commercial zinc; -- so called because certain of its compounds are darkened by exposure to light.

Chemistry in its relations to actinism.

A record made by the actinograph.

An instrument for measuring and recording the variations in the actinic or chemical force of rays of light.

Having the form of rays; radiated, as an actinia.

A bright green variety of amphibole occurring usually in fibrous or columnar masses.

Of the nature of, or containing, actinolite.

The science which treats of rays of light, especially of the actinic or chemical rays.

One of the radial segments composing the body of one of the C/lenterata.

An instrument for measuring the direct heating power of the sun's rays. An instrument for measuring the actinic effect of rays of light.

Pertaining to the measurement of the intensity of the solar rays, either (a) heating, or (b) actinic.

The measurement of the force of solar radiation.

filamentous or rod-shaped bacteria.

branched gram-positive bacteria, often found in soil, some of which are pathogenic for humans and animals.

of or pertaining to actinomycetes.

any of various red antibiotics isolated from soil bacteria with a three-ring heterocyclic nucleus with an attached peptide chain.

The most well-known of the actinomycins (C62H86N12O16), a class of antibiotics which act by binding to DNA and inhibiting synthesis of RNA; they act agains gram-positive bacteria and many eukaryotic organisma. Actinomycin D has been used in human medicine to treat certain tumors.

A chronic infectious disease of cattle and man due to infection with actinomycetes, especially by Actinomyces bovis in cattle and by Actinomyces israeli or Arachnia propionica in man. It is characterized by hard swellings usually in the mouth and jaw. In man the disease may also affect the abdomen or thorax. In cattle it is called also lumpy jaw or big jaw.

Of or pertaining to actinomycosis.

an order comprising parasites of worms.

a type of parasite of worms.

An apparatus for the production of sound by the action of the actinic, or ultraviolet, rays.

Pertaining to, or causing the production of, sound by means of the actinic, or ultraviolet, rays; as, actinophonic phenomena.

Having straight projecting spines.

protozoa having stiff rodlike radiating pseudopods.

heliozoans; radiolarians.

The entire body of a c/lenterate.

One of the bones at the base of a paired fin of a fish.

The mouth or anterior opening of a c/lenterate animal.

A peculiar larval form of Phoronis, a genus of marine worms, having a circle of ciliated tentacles.

A group of C/lenterata, comprising the Anthozoa and Ctenophora. The sea anemone, or actinia, is a familiar example.

Of or pertaining to the Actinozoa.

One of the Actinozoa.

A kind of embryo of certain hydroids (Tubularia), having a stellate form.

A process or condition of acting or moving, as opposed to rest; the doing of something; exertion of power or force, as when one body acts on another; the effect of power exerted on one body by another; agency; activity; operation; as, the action of heat; a man of action.

That may be the subject of an action or suit at law; as, to call a man a thief is actionable.

In an actionable manner.

A shareholder in joint-stock company.

Void of action.

naval battle where Antony and Cleopatra were defeated by Octavian's fleet under Agrippa in 31 BC.

To make active.

treated with aeration and bacteria to aid decomposition; -- of sewage

same as activation{1}.

the process of making active. making active and effective (as a bomb).

any agency bringing about activation; (Biol.) a molecule that increases the activity of an enzyme or a protein that increases the production of a gene product in DNA transcription.

Having the power or quality of acting; causing change; communicating action or motion; acting; -- opposed to passive, that receives; as, certain active principles; the powers of the mind.

In an active manner; nimbly; briskly; energetically; also, by one's own action; voluntarily, not passively.

The quality of being active; nimbleness; quickness of motion; activity.

a policy of taking direct and militant action to achieve a political or social goal.

one who is aggressively active on behalf of a cause.

advocating a cause or engaged in activism

The state or quality of being active; nimbleness; agility; vigorous action or operation; energy; active force; as, an increasing variety of human activities.

Without action or spirit.

A stuffed jacket worn under the mail, or (later) a jacket plated with mail.

One who acts, or takes part in any affair; a doer.

A female actor or doer.

one of the books of the Christian New Testament describing the activities of Christ's apostles after his death.

Something actually received; real, as distinct from estimated, receipts.

One who deals with or considers actually existing facts and conditions, rather than fancies or theories; a realist; -- opposed to idealist.

A making actual or really existent; giving the appearance of reality.

To make actual; to realize in action.

changed from potential to actual; as, saw his worst fears actualized.

Actively.

Quality of being actual; actuality.

Of or pertaining to actuaries; as, the actuarial value of an annuity.

A registrar or clerk; -- used originally in courts of civil law jurisdiction, but in Europe used for a clerk or registrar generally.

Put in action; actuated.

moved to action

causing motion or action or change

A bringing into action; movement.

One who actuates, or puts into action.

Very active.

Abundant activity.

Action.

Tendency or impulse to act.

Sharpened; sharp-pointed.

Act of sharpening.

The act of sharpening.

Sharpness or acuteness, as of a needle, wit, etc.

A small spiny outgrowth on the wings of certain insects.

Having a sting; covered with prickles; sharp like a prickle.

Having a sharp point; armed with prickles; prickly; aculeate.

Like a prickle.

Having small prickles or sharp points.

Aculeate.

A prickle growing on the bark, as in some brambles and roses.

Quickness of perception or discernment; penetration of mind; the faculty of nice discrimination.

To end in, or come to, a sharp point.

A sharpening; termination in a sharp point; a tapering point.

Terminating in a flat, narrow end.

Characterized by acumen; keen.

A mode of arresting hemorrhage resulting from wounds or surgical operations, by passing under the divided vessel a needle, the ends of which are left exposed externally on the cutaneous surface.

See Acupuncture.

To treat with acupuncture.

See Accustomance.

Acute-angled.

To give an acute sound to; as, he acutes his rising inflection too much.

Having acute angles; as, an acute-angled triangle, a triangle with every one of its angles less than a right angle.

In an acute manner; sharply; keenly; with nice discrimination.

The quality of being acute or pointed; sharpness; as, the acuteness of an angle.

Having sharp-pointed leaves.

Having acute lobes, as some leaves.

The twisting of an artery with a needle to arrest hemorrhage.

Not cyclic; not disposed in cycles or whorls Of a flower, having its parts inserted spirally on the receptacle. Having an open-chain structure; aliphatic.

An acid radical, as acetyl, malonyl, or benzoyl. An acyl radical can be depicted as R-CO-, where -CO- is the carbonyl group, and R is the group that characterizes the acyl moiety.

To compel; to drive.

Without fingers or without toes. Without claws on the feet (of crustaceous animals).

the Babylonian god of storms and wind.

An old saying, which has obtained credit by long use; a proverb.

Pertaining to an adage; proverbial.

A piece of music in adagio time; a slow movement; as, an adagio of Haydn.

The name given in the Bible to the first man, the progenitor of the human race.

North American orchid (Aplectrum hyemale) bearing a single leaf and yellowish-brown flowers.

same as adamancy.

obstinacy.

A stone imagined by some to be of impenetrable hardness; a name given to the diamond and other substances of extreme hardness; but in modern mineralogy it has no technical signification. It is now a rhetorical or poetical name for the embodiment of impenetrable hardness.

Of adamant; hard as adamant.

Made of adamant, or having the qualities of adamant; incapable of being broken, dissolved, or penetrated; as, adamantine bonds or chains.

Next to the ambulacra; as, the adambulacral ossicles of the starfish.