An Etymological Dictionary of the German Language/Annotated/strotzen
strotzen, verb, ‘to be puffed up, teem, boast of,’ from the equivalent late Middle High German strotzen, weak verb. The Teutonic root strū̆t, which is not widely diffused, appears in English strut (to which Old Icelandic þrútenn, ‘swollen,’ is allied; compare Old Icelandic þjórr, equivalent to High German Stier). To this Modern High German Strauß, ‘contest,’ with the evolved meaning ‘to swell with anger,’ and its cognates are allied?.