nuclear reactor |
any of several devices that initiate and control a nuclear fission chain reaction to produce energy and material used for experimental and medical purposes. |
nuclear winter |
a hypothesized result of a major nuclear war, wherein massive cloud covers of dust and smoke would block out sunlight, lowering the earth's temperature and destroying most living things. |
nuclease |
any of several enzymes that facilitate the hydrolysis of nucleic acids. |
nucleate |
possessing a nucleus or nuclei. [4 definitions] |
nuclei |
pl. of nucleus. |
nucleic acid |
any of a group of essential, complex acids comprising the genetic material of all living cells; DNA or RNA. |
nucleolus |
a small spherical body in the nucleus of a cell, consisting of protein and RNA. |
nucleon |
a proton or neutron, esp. as a component of an atomic nucleus. |
nucleonics |
(used with a sing. verb) the science or technology having to do with atomic nuclei, esp. with nuclear energy. |
nucleophile |
a substance that donates electrons or has an affinity for atomic nuclei. |
nucleotide |
any of a class of esters on which nucleic acids are based. |
nucleus |
the central, essential, or highly concentrated part around which other parts are grouped. [4 definitions] |
nuclide |
a category of atoms, all of which have the same number of protons and neutrons and the same nuclear energy. [2 definitions] |
nude |
not wearing clothes; naked. [5 definitions] |
nudge |
to push gently or touch, esp. with the elbow and esp. so as to attract attention. [4 definitions] |
nudism |
the belief in or the practice of not wearing clothes, esp. with others of both sexes in designated settings. |
nudity |
the condition or fact of being unclothed; nakedness. |
nuée ardente |
a thick volcanic cloud that explodes and pours down the sides of a volcano. |
nugatory |
having little or no real importance or value; trifling. [2 definitions] |
nugget |
a small, solid lump, esp. of a precious metal such as gold. [2 definitions] |
nuisance |
someone or something that is annoying or troublesome. |