| Australia |
the smallest continent. Australia is southeast of Asia, between the Indian and Pacific Oceans. It is in the Eastern Hemisphere. [2 definitions] |
| Australian |
of or having to do with Australia, or its people or languages. [2 definitions] |
| Austria |
a country in central Europe. Vienna is the capital of Austria. |
| authentic |
real, genuine, or true. |
| author |
the writer of a book, play, story, or other written work. |
| authoritative |
having or showing authority. [2 definitions] |
| authority |
the right or power to give orders, make decisions, or control people. [3 definitions] |
| authorize |
to give authority to. [2 definitions] |
| autism |
a human disorder that begins to show itself in early childhood. Autism is marked by problems with language learning, language use, and social interaction. |
| auto |
short form of "automobile," a vehicle powered by a motor that uses gasoline or other fuel; car. |
| auto- |
a prefix that means done by oneself or itself. |
| autobiography |
the story of a person's life written or told by that person. |
| autograph |
the name of a person, especially a famous person, written in his or her own handwriting. [2 definitions] |
| automated teller machine |
a computerized machine used for banking. |
| automatic |
working or operating by itself. [2 definitions] |
| automation |
the use of machines rather than people to do work. |
| automobile |
a vehicle with four wheels that is powered by a motor that uses gasoline or other fuel; car. An automobile is used on roads to carry people. |
| autopsy |
a medical examination of a dead body to find the cause of death. |
| autumn |
the season of the year between summer and winter; fall. |
| auxiliary |
serving as an extra means of support; additional. [3 definitions] |
| auxiliary verb |
a verb used with a main verb to complete the main verb's meaning. Some examples of auxiliary verbs are "have" in "I have escaped" and "should" in "You should go." |