P.S., post scriptum=Postscript, written after.

Ps., Psa. Psalms.

pseud. Pseudonym.

P.T. Pupil Teacher.

p.t. Post-town.

P.T.O. Please turn over.

Pub. Doc. Public Document.

P.W.D. Public Works Department.

pwt. Pennyweight.

P. & O. Peninsular and Oriental Company.