proton

noun

1. (particle)A positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element, composed of two up quarks and a down quark.

   “The dance of the electrons about the prota, each electron and each proton consisting of a series of waves occupying the whole of the limited universe and obeying the laws of nature as they pass, is known to all.”

2. (particle)A positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element, composed of two up quarks and a down quark.
3. (obsolete)Synonym of primordium.

   “It is a well authenticated fact that, in the case of section of a peripheral nerve, the nuclei of the sheath of Schwann pass to the centre of the lumen and form the protoplasmic prota of the segments of the new nerve[…]. From studies of the development of the olfactory organs in reptiles, as reported briefly in earlier numbers of this Journal, the writer has been abundantly convinced of the truth of Beard’s statement that the olfactory prota arise from the skin[…].”

   “This paper constituted the proton (the primordium, or ‘Anlage,’ if you prefer) of my own subsequent contributions, and likewise, so far as I knew at the time, of the simplified nomenclature in America.”