nuclear

Etymology

From Latin nū̆cleus, a contraction of the adjective nuculeus, masculine of feminine nuculea (“pertaining to a small nut”) from nucula + adjectival suffix -eus, -ea, -eum. The Latin nucula + -āris adds up to nuculāris, a term that in English becomes nucular; the Latin nuculea + -āris, becomes Latin nuculeāris (“relative to what pertains to small nut”), later contracted into nuclear (English surface analysis, nucle(us) + -ar = nucle- + -ar). Compare muscle and Latin mūsculus; muscular and mūsculāris.

adj

1. Pertaining to the nucleus of an atom.
2. Involving energy released by nuclear reactions (fission, fusion, radioactive decay).
   a nuclear reactor
   nuclear technology
3. Relating to a weapon that derives its force from rapid release of energy through nuclear reactions.
   a nuclear explosion
   a nuclear power
4. (by extension, figurative, of a solution or response) Involving an extreme course of action.
   nuclear option, nuclear solution
   The states begging for aid get turned away; and sharp cuts in government employment, spending, and, eventually, pension payments are the only alternative future, beyond the nuclear solution of defaulting on our debt. 2011, Todd Lipscomb, Re-Made in the USA
   The nuclear approach is the simpler of the two. When two constraints conflict, you can kill one of them. 2013, Erica Sadun, iOS Auto Layout Demystified, page 150
   Republicans have taken the historic step of triggering the so-called "nuclear option" to change the rules of the Senate and push through Donald Trump's pick for the Supreme Court, after Democrats blocked the nomination. April 6, 2017, Mythili Sampathkumar, “Democrats filibuster forces Republicans to use 'nuclear option to confirm Trump's Supreme Court pick”, in The Independent
5. (biology) Pertaining to the nucleus of a cell.
   However, the DNA in a bacterial cell is a single circular molecule and there is no separate nuclear compartment. 2011, Terence Allen, Graham Cowling, The Cell: A Very Short Introduction, Oxford, page 17
6. (archaic) Pertaining to a centre around which something is developed or organised; central, pivotal.

noun

1. Nuclear power.
   The growth in wind capacity at first lagged behind the expansion of nuclear installations, but then it started to grow faster and is now outpacing nuclear. 2015, Vital Signs Volume 22: The Trends That Are Shaping Our Future, The Worldwatch Institute
2. Nuclear weapon
   Admiral Burke believed that we would be able to beat off an amphibious attack, even if staged in conjunction with heavy aerial bombing, long enough to refer back to Washington and obtain authorization to use nuclears. 1958, Foreign Relations of the United States (page 118)