| HIGGSBOSON | In physics, an elementary particle with zero spin and mass greater than zero, discovered in 2012 (5,5) |
| AXION | Hypothetical subatomic particle with zero spin and electric charge, thought to constitute dark matter (5) |
| POSITRON | In physics, an elementary particle also called an antielectron (8) |
| PIONS | Subatomic particles with zero spin |
| NEUTRON | Elementary particle with zero charge (7) |
| BOSON | Higgs ___ (elementary particle discovered in 2012) |
| STYX | Moon of Pluto discovered in 2012 |
| NEUTRONS | Elementary particles with zero electric charge and slightly larger mass than protons |
| SINGLET | One-piece garment for wrestling; a vest; or, a quantum state with zero spin (7) |
| PROTON | An elementary particle with positive charge (6) |
| GREATFAMINE | This tragedy started in Ireland in 1845 and ended in 1849. It was caused by late blight, which ruined the potato crop, and it resulted in about one million deaths and mass emigration. |
| NEUTRINO | In physics, a particle with zero charge and very small mass (8) |
| PERMEAMETER | In physics, an instrument used to measure the magnetic permeability of a substance or object (11) |
| SPIN | In physics, the intrinsic angular momentum of an elementary particle or nucleus (4) |
| TAO | 1975 book "The ___ of Physics: An Exploration of the Parallels Between Modern Physics and Eastern Mysticism" |
| ISOTOPS | In physics, atomic nuclei with the same atomic numbers and mass as others but different energy state |
| NEUTRINOS | An uncharged particle with zero mass when at rest (9) |
| ELLIPSE | A shape with eccentricity greater than 0 and less than 1 (7) |
| STRAIN | Breed or stock; a trait; a melody; deformation of a material from stress in physics; an intense effort; or, a sprain incurred as a result of said wrench (6) |
| MUON | Elementary particle with a mass 207 times that of an electron |
