(|)trī|fen ə l, -fēn-+...- noun
Etymology: triphenyl- + tetrazolium
: a colorless crystalline salt C(C 6 H 5 ) 3 N 4 Cl that is obtained by oxidative ring closure of triphenylformazan and that gives back triphenylformazan on reduction (as by enzymes or reducing sugars) so that the red color formed can serve as a stain for tissues, as a test for viability (as of seeds), and as an analytical reagent — called also tetrazolium chloride, 2,3,5-triphenyltetrazolium chloride, TTC