tenacity
noun
°The quality or state of being tenacious; as, tenacity, or retentiveness, of memory; tenacity, or persistency, of purpose.
°The quality of bodies which keeps them from parting without considerable force; cohesiveness; the effect of attraction; – as distinguished from brittleness, fragility, mobility, etc.
synonyms: retentiveness, persistency, cohesiveness, adhesiveness more» , viscosity