Bible Dictionaries
Alpha Rays

Webster's Dictionary

Rays of relatively low penetrating power emitted by radium and other radioactive substances, and shown to consist of positively charged particles (perhaps particles of helium) having enormous velocities but small masses. They are slightly deflected by a strong magnetic or electric field.

Bibliography Information
Webster, Noah. Entry for 'Alpha Rays'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​a/alpha-rays.html. 1828.