| open admissions |
the policy of admitting any student who desires to attend a university, regardless of proficiency. |
| open air |
the outdoors. |
| open chain |
in chemistry, a linear series of covalent atoms not joined at the ends into a cycle, such as an aliphatic compound. |
| open circuit |
an electrical circuit that is broken and carries no current. |
| open city |
a city in a war zone that is officially declared to be demilitarized and open to enemy occupation, and is thus rendered immune, by international law, to attack or bombardment. |
| open door |
free and unrestricted admission or access; unhindered opportunity. [2 definitions] |
| open house |
a time during which one's home is open to friends and relatives for informal visits. [2 definitions] |
| open letter |
a letter, usu. of protest or criticism, that is addressed to a specific individual or group but published in a newspaper or magazine to gain public attention. |
| open market |
a market in which there are no official restrictions on prices or participation; free market. |
| open primary |
a primary election in which voters need not declare party membership. |
| open punctuation |
punctuation characterized by the use of few punctuation marks. |
| open sea |
that expanse of an ocean away from any coastlines; high seas. |
| open secret |
something supposed to be secret but actually widely known. |
| open sentence |
in mathematics education, a simple mathematical equation or inequality in which one quantity is unknown, such as 2 + ? = 5. |
| open sesame |
in The Arabian Nights, the magic words that open the door of the robbers' den. [2 definitions] |
| open shop |
a business or factory in which a union represents the workers, although union membership is not necessary for employment. |
| open stock |
a type of merchandising in which single pieces of goods usu. sold in sets, such as flatware, glassware, or china, are kept in stock to be sold individually as replacement or supplements. |
| open up |
(informal) to speak revealingly, esp. of oneself. [4 definitions] |
| open-air |
being, done, or occurring outdoors. |
| open-and-shut |
(informal) not requiring much deliberation; not presenting ambiguity or difficulty; immediately obvious. |