| one-step |
a ballroom dance that consists of an unbroken series of quick walking steps and is danced to ragtime music. [3 definitions] |
| one-time |
former. [2 definitions] |
| one-to-one |
matching or corresponding, as each element of one set with a specific element of another. |
| one-track |
concerned exclusively with one idea, topic, or the like. [2 definitions] |
| one-two |
in boxing, a sequence of two punches, such as a quick jab with the left fist followed immediately by a hard punch with the right. |
| one-up |
to surpass (someone) in order not to be bettered or lose face. |
| one-upmanship |
the method, practice, or habit of always trying to surpass or gain an advantage over others so as not to be bettered. |
| one-way |
proceeding in or restricting motion to a single direction. [3 definitions] |
| on fire |
burning; in flames. [3 definitions] |
| on foot |
by walking. |
| ongoing |
existing continuously from some time in the past into the present. |
| on guard |
alert and prepared. |
| on hand |
readily available. |
| on her beam-ends |
of a ship, tipping so far to one side as to be nearly capsizing. |
| on hold |
waiting to complete a telephone call. |
| on ice |
(informal) in reserve. |
| onion |
a round, sharp-tasting bulb used extensively in cooking and as a flavoring. [2 definitions] |
| onion dome |
a cupola in a shape similar to that of an onion with a pointed top, often used in Russian church architecture. |
| onionskin |
a translucent paper, often used for typing. |
| on (one's) last legs |
having very little remaining energy, strength, hope, or ability to function; liable to collapse or die. |
| online |
connected to or reached through a computer or computer network. [3 definitions] |