| on guard |
alert and prepared. |
| on hand |
readily available. |
| onion |
a round, sharp-tasting bulb used extensively in cooking and as a flavoring. [2 definitions] |
| 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] |
| only |
solely; as the sole instance. [8 definitions] |
| on occasion |
now and then; irregularly. |
| on one's toes |
(informal) alert and ready to respond or act. |
| on purpose |
deliberately; intentionally. |
| onset |
the early stage; beginning. [2 definitions] |
| on tap |
ready to be served from a cask, as beer or ale. [2 definitions] |
| Ontario |
a south central Canadian province on the Great Lakes. [2 definitions] |
| on the air |
broadcast on radio or television. |
| on the average |
usually; ordinarily. |
| on the ball |
acting with efficiency and competence. [2 definitions] |
| on the blink |
not functioning; needing repair. |
| on the contrary |
in contradiction to something already said. |
| on the dot |
(informal) exactly on time; punctually. |
| on the double |
(informal) right away; immediately. |
| on the house |
free, as a gift from a business establishment. |
| on the mend |
getting better, esp. in health; recuperating. |