Browse Dictionary by Letter

Comprehensive
Dictionary Suite
Help
Help
Help
A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z
actinium a radioactive chemical element of the rare-earth group that has eighty-nine protons in each nucleus. (symbol: Ac)
actinogen any of the radioactive chemical elements.
actinoid having a radial or star-shaped form, as certain sea creatures.
actinomycin any of several antibiotics derived from soil bacteria that work against certain other bacteria and fungi.
actinomycosis an infectious disease of animals and humans that is caused by parasites and produces abscesses, esp. in the jaws.
actinozoan see anthozoan.
action something that is done, is being done, or will be done. [8 definitions]
actionable providing legitimate grounds for legal action.
action-adventure a genre of films, video games, and the like having an exciting undertaking involving risk and danger as its main story line, and involving one or more heroes engaged in a series of physical challenges. [2 definitions]
actionless combined form of action.
action movie a film whose story line focuses on conflict and fast-paced activity, esp. involving physical violence, feats of strength and agility, and chase scenes.
action-packed of a film, video, story, or the like, filled with scenes depicting action, danger, and exciting events.
action verb a verb that shows its subject performing some action. "Run," "eat," "fly," and "sing" are examples of action verbs.
activate to initiate action in; make active. [5 definitions]
activated carbon a form of very porous and thus very absorbent carbon, produced by heating charcoal so as to empty out contained gases, and used to absorb other gases, recover solvents, deodorize, and the like; activated charcoal.
activated charcoal see activated carbon.
activation code a set of numbers sent by a website to a user's email so that the website can verify the user's email address and comply with the user's request to begin a new service or change personal information. Once received, the user enters the code into the provided box on the website so that fulfillment of the user's request can begin.
active constantly doing something; busy; energetic. [6 definitions]
active duty the status of full-time service or work, esp. in the military.
active immunity an organism's immunity to a disease because of its production of antibodies.
actively in a way that involves making an effort, taking action, or participating; not passively.