A primitive root; to glare, i.e. Be dazzling white -- be whiter.
H6705. tsachach
[צָחַח] verb be dazzling (צַחְצַח ᵑ7 polish; Syriac be scorched, Aph`el declare in writing (make clear), clarus, lucidus, fulgidus; , , smooth, plain); —
Qal Perfect3plural מֵחָלָב צַחוּ Lamentations 4:7 ("" מִשֶּׁלֶג זַכּוּ), they are more dazzling (i.e. whiter) than milk (of effeminate skin).