GC: n
CT: Nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
Fusion reactions take place in a state of matter called plasma — a hot, charged gas made of positive ions and free-moving electrons with unique properties distinct from solids, liquids or gases.
The sun, along with all other stars, is powered by this reaction. To fuse in our sun, nuclei need to collide with each other at extremely high temperatures, around ten million degrees Celsius. The high temperature provides them with enough energy to overcome their mutual electrical repulsion. Once the nuclei come within a very close range of each other, the attractive nuclear force between them will outweigh the electrical repulsion and allow them to fuse. For this to happen, the nuclei must be confined within a small space to increase the chances of collision. In the sun, the extreme pressure produced by its immense gravity creates the conditions for fusion.
S: IAEA – https://www.iaea.org/newscenter/news/what-is-nuclear-fusion (last access: 9 May 2025)
N: 1. – nuclear (adj): 1846, “of or like the nucleus of a cell,” from nucleus + -ar, probably by influence of French nucléaire. Use in atomic physics is from 1914; of weapons, from 1945. Hence nuclear physics (1933), nuclear energy (1941), nuclear war (1954). Alternative adjective nucleal is recorded from 1840.
– fusion (n): 1550s, from Middle French fusion, from Latin fusionem (nominative fusio) “an outpouring, effusion,” noun of action from fusus, past participle of fundere “pour, melt”. In nuclear physics sense, first recorded 1947.
2. the union of atomic nuclei to form heavier nuclei resulting in the release of enormous quantities of energy when certain light elements unite—called also nuclear fusion.
3. The combination of two light nuclei to form a heavier nucleus (and perhaps other reaction products) with release of some binding energy.
4. nuclear fusion: term standardized by ISO. Source 4, fiche 1, Anglais, Observation 1 – nuclear%20fusion
5. fusion: term standardized by NATO.
S: 1. Etymonline – http://www.etymonline.com/index.php?allowed_in_frame=0&search=nuclear+fusion&searchmode=none (last access: 18 December 2014). 2. MW – http://www.merriam-webster.com/medical/fusion (last access: 18 December 2014). 3 to 5. TERMIUM PLUS (last access: 18 December 2014).
SYN: fusion
S: MW – http://www.merriam-webster.com/medical/fusion (last access: 18 December 2014); TERMIUM PLUS (last access: 18 December 2014).
