/ Thesaurus / R Synonyms of rein in Find synonyms for: Verb1. rein, rein in, stop, haltusage: stop or slow up one's horse or oneself by or as if by pulling the reins; "They reined in in front of the post office"2. harness, rein in, draw rein, rein, control, commandusage: control and direct with or as if by reins; "rein a horse"3. rein, rein in, stopusage: stop or check by or as if by a pull at the reins; "He reined in his horses in front of the post office"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: abscond Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language