| atomic pile |
see "nuclear reactor." |
| atomic theory |
any of several theories concerning the structure, properties, or behavior of atoms. [2 definitions] |
| atomic weight |
the average weight of one atom of a given element, expressed in atomic mass units. |
| atomism |
a theory that all matter is composed of small, indivisible particles called atoms, which in modern form is called atomic theory. [2 definitions] |
| atomistic |
of or relating to atoms or atomism. [2 definitions] |
| atomize |
to divide into atoms. [3 definitions] |
| atomizer |
a device that converts a liquid, esp. a medicine or perfume, into a spray. |
| atom smasher |
see "accelerator." |
| atonal |
in music, composed without a fixed key or scale. |
| at once |
at the same time. [2 definitions] |
| atone |
to make reparation for a sin, crime, error, or the like (usu. fol. by "for"). [2 definitions] |
| at one |
in a state of harmony or accord. |
| atonement |
the act of atoning; reparation. [3 definitions] |
| at one's elbow |
close by. |
| at one's fingertips |
readily available. |
| at one's heels |
in close pursuit. |
| at one's leisure |
when the time is convenient; when one has spare time. |
| atop |
at or on the highest point. [2 definitions] |
| atopic |
of or relating to a genetic tendency to develop allergic reactions. |
| atopy |
a genetic tendency to develop allergic reactions that is typically associated with a heightened immune response to certain allergens. |
| -ator |
one that does (such) a thing or acts in (such) a way. |