adj.c.1500, from French infatigable (15c.), from Latin infatigabilis, from in- "not, opposite of" (see in- (1)) + fatigabilis, from fatigare "to weary" (see fatigue). if (window.googletag) {googletag.cmd.push(function() { googletag.display('dcomMobileSERPDisplayTopAd-300x250'); });} else {console.error('googletag not defined, dcomMobileSERPDisplayTopAd-300x250');}