pi

n 1 the sixteenth letter of the Greek alphabet (, ), represented in English spelling by `p' 希腊字母表的第十六个字母（）, 英语拼写中用 p. 2 (geometry 几) symbol () representing the ratio of the circumference of a circle to its diameter (ie 3.14159) 圆周率（即3.14159）.

phrenetic, phrenological, phrenologist, phrenology, phut, phylum, physi(o)-, physical, physical exercises, physically, physician, physicist, physics, physiognomy, physiological, physiologist, physiology, physiotherapist, physiotherapy, physique, pianissimo, pianist, piano, piano-accordion, pianola (also Pianola), piastre (US piaster), piazza, pibroch, pica, picador, picaresque, Piccadilly, piccalilli, piccaninny, piccolo, pick, pick off, pick on sb, pick out, pick sb/sth out,