Iskani niz je bil najden v PREVODIH:
čvrstoća
en consistence, fastness, firmness, fixture, hardness, solidity, solidness, soundness, steadfastness, steadiness, strenght, strength, temper, thickness, toughness
jačina
en fixture, intensity, poignancy, power, raciness, rankness, richness, severity, shade, sharpness, sinew, strenght, strength, substantiality, tenacity, vigor, vigour, violence, volume