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From Transwiki

The inverse of Q is the dissipation factor (δ). Thus, δ = ESR/XC and the higher the ESR the more losses in the capacitor and the more power we dissipate. If too much energy is dissipated in the capacitor, it heats up to the point that values change (causing drift in operation) or failure of the capacitor

Some times the dissipation factor is also called as Tan-d. Thus, Tan-d = 1/(2*pi*f*C*R).

where,

      pi = 22/7
       f = frequency
       C = capacitor
       R = resistance ( of capacitor ) 
           generally resistance will be in million mega ohms
           and you can't measure it in an ordinary multimeter.