: also, before a vowel, rect-
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
Mifflin Harcourt. Published by Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'recti-'
LL < L rectus,
straight, right < pp. of regere,
to lead straight, direct, guide, rule: see right