Latin Prefixes and Their Meanings: A Study Guide for Vocabulary Building

Pre-

before ex) preview, prehistoric

Semi-

half, partly, ex) semi-circle, Semi-conscious

Ob-

toward, against, in the way ex: Obstacle, obstruct

Pro-

forward, for, ex) proceed, promote

Per-

through, thoroughly, ex) perfect, Permeate

Se-

apart, aside ex) separate, secure

Sub-

under, below ex) submarine, subway

Re-

again, back,ex) redo, return

Trans-

across, beyond ex) transport, transform

Post-

after ex) post war, postscript

retro-

backward, ex) retrospect, retroactive