the gum, the method of separation (perforation, regulating), any overprints on the stamp, any security markings, under prints or perforated initials ("perfins"), and the study of philatelic fakes and forgeries.
What does PI stand for?
PI stands for Perforated Initials (philately)
This definition appears very rarely and is found in the following Acronym Finder categories:
- Organizations, NGOs, schools, universities, etc.
See other definitions of PI
We have 126 other meanings of PI in our Acronym Attic
- Paternity Index
- Payload Integrator
- PCNA (Proliferating Cell Nuclear Antigen) Labeling Index
- Pearl Islands (Hawaii)
- Penile Implant
- Pentium I (Intel)
- Per Inch
- Per Inquiry
- Perception Immédiate (French)
- Perceptually Impaired