core; heart (of the matter); point; crux; kernel
kernel; core; nucleus; center; centre
nuclear attack; nuclear strike
core (of planets, stars, galaxies, etc.); nucleus (of comets, galaxies, etc.)
nuclear fission; karyokinesis (division of a cell nucleus during mitosis or meiosis)
atomic fuel; nuclear fuel
non-nuclear; anti-nuclear
nuclear magnetic resonance; NMR
total abolition of nuclear weapons
infectious mononucleosis; mono; glandular fever
possession of nuclear weapons
nucleus accumbens (part of the forebrain)
nuclear allergy; antipathy shown by the Japanese to nuclear weapons
basal ganglia; basal nuclei
abandoning nuclear weapons, etc.; nuclear disposal
nuclear development program; nuclear program
nuclear watchdog (i.e. the IAEA)
fissility; fissile; fissionable
Joint Comprehensive Plan of Action; Iran nuclear deal; Iran deal
eukaryotic microorganism; eucaryotic microorganism
nuclear magnetic resonance imaging; NMRI
nuclear reprocessing plant
nuclear defenses; nuclear defences
nuclear issue; nuclear problem
superheavy nucleus; ultraheavy nucleus
suspicion of having (or to be making) nuclear weapons
(spent) nuclear fuel storage pool
disintegration of a cell nucleus
nuclear fuel rod; nuclear rod
nuclear bonding; nuclear force
hijacking of nuclear material
accent nucleus; accent kernel