As a verb perfix
is (obsolete) to fix surely; to appoint.
As a noun perfin is
(philately) perforated initial; a series of small holes punched into a stamp and forming a letter, series of letters or other design for the purpose of preventing the unauthorized use of the stamps.
perfin
English
Noun
(
en noun)
(philately) Perforated initial; a series of small holes punched into a stamp and forming a letter, series of letters or other design for the purpose of preventing the unauthorized use of the stamps.
A stamp marked with perforated initials.