per

through, thoroughly

Spelled per · per 'through, thoroughly'

Latin per carries movement through: drills perforate walls, smells permeate rooms, and a mood can pervade an entire gathering.

Words built from it

perfunctory — done as a routine duty, with little care or interest
Latin perfungi 'carry out, finish': per- 'through' + fungi 'perform' → perfunctorius → perfunctory
permeate — to spread through every part of something
Latin permeare: per- 'through' + meare 'go, pass' → permeate
perforate — to make a hole or holes through something
Latin perforare: per- 'through' + forare 'bore, pierce' → perforate
perennial — lasting for years or returning repeatedly
Latin perennis 'lasting through the year': per- 'through' + annus 'year' → perennial
pervade — to spread throughout a place or thing
Latin pervadere: per- 'through' + vadere 'go' → pervade
persist — to continue despite difficulty or opposition
Latin persistere: per- 'thoroughly' + sistere 'stand firm' → persist
perfect — complete and without faults
Latin perficere 'complete': per- 'thoroughly' + facere 'make, do' → perfectus → perfect

perilous — Built from peril, from Latin periculum 'danger'; its initial per is not this prefix.