P, the 15th letter and 11th consonant of the alphabet; the sound of which is formed by expressing the breath somewhat more suddenly than in forming the sound of b; in other respects these two sounds are pretty much alike, and are often confounded one with another. When p stands before t or s, its sound is lost; as in the words psalms, psychology, problematic, ptisan, &c. When placed before b, they both together have the sound ps; as in philosophy, physics, &c.
P and B are so like each other, that Quintilian declares, that in the word obtinuit, his reason required him to put a b, but that his ears could hear nothing but a p, obtinuit: hence in ancient inscriptions and old glossaries, it appears that these two letters have often been confounded. Several nations still pronounce one for the other, the Welch and Germans particularly, who say, ponum vinum, for bonum vinum. Plutarch observes, it was usual for those of Delphi to say salus for salus, hexon for hexon; and among the Latins, as often as an s followed, the b was changed into a p, as scribo, scripsi.
As an abbreviation, P stands for Publius, Pondo, &c. P. A. DIG. for Patria Dignitas; P. C. for Patrie Conscripti; P. F. for Publii Filius; P. P. for Propositum, or Propositum publice; P. R. for Populus Romanus; P. R. S. for Pratoris sententia, P. R. S. P. for Pratis provincie.
P. M. among astronomers, is frequently used for post meridiem, or "afternoon;" and sometimes for post mane, "after the morning, i. e. after midnight." P was also used among the ancients as a numeral letter, signifying the same with the G, viz. a hundred; according to the verse of Ugitio,
P similem cum G numerum monstratur habere.
Though Baronius thinks it rather flood for seven.
When a dash was added a-top of P, it stood for four hundred thousand.
St Jerome observes, on Daniel, that the Hebrews had no P; but that the ph served them instead thereof: adding that there is but one word in the whole Bible read with a P, viz. opadno. The Greek φ signified 80. On the French coins, P denotes those that were struck at Dijon.
In the Italian music, P stands for piano, or "softly;" and P. P. P. for pianissimo, or "very softly."
Among physicians, P stands for pusil, or the eighth part of an handful; P. A. partes aequales, or equal parts of the ingredients; P. P. signifies pulvis patrum, or Jesuit's bark in powder; and ppt. preparatus or prepared.