| Lengthen 1. (v. t.) To extent in length; to make longer in extent or duration; as, to lengthen a line or a road; to lengthen life; -- sometimes followed by out. 2. (v. i.) To become longer. Thesaurus Entries add to, aggrandize, amplify, augment, boost, broaden, build, build up, continue, dawdle, drag out, draw, draw out, dwell on, elongate, enlarge, exalt, expand, extend, fatten, fill out, hike, hike up, hold, increase, inflate, jack up, jump up, keep, keep alive, keep going, keep up, lengthen out, let out, linger on, maintain, maximize, parlay, perpetuate, preserve, procrastinate, produce, prolong, prolongate, protract, pull, put up, pyramid, raise, retain, spin out, strain, stretch, stretch out, string out, sustain, tauten, temporize, tense, thicken, tighten, up |