From an unused root meaning to be prickly; a thorn; hence, a cactus-hedge -- thorn.
[צֵן] noun [masculine] thorn? barb?; — pluralצִנִּים Proverbs 22:5 (+ מַּחִים); וְאֶלמִֿצִּנִּים Job 5:5 from (behind) thorns (a protecting thorn hedge, so Di), but very dubious; CheJQ July, 1897, 576 strike out as doublet of צַמִּים; BevJPhil. xxvi. 305 proposes צִנִּים וְאִנָם [and as to their wealth, barbs (? barbed spears) takeit].