In Ancient Greek grammar, a perispomenon (περισπώμενον) is a word with a high-low pitch contour on the last syllable, indicated in writing by a circumflex accent mark. A properispomenon has the same kind of accent, but on the penultimate syllable.
Examples:
Etymology
Peri-spṓmenon means "pronounced with a circumflex", the neuter of the present passive participle of peri-spáō "pronounce with a circumflex" (also "draw off"). Pro-peri-spṓmenon adds the prefix pró "before". περισπωμένη is the Greek name for the accent mark (⟨῀⟩).
References
Perispomenon Wikipedia(Text) CC BY-SA