consistency (grease) - a basic property describing the softness or hardness of a grease, i.e., the degree to which a grease resists deformation under the application of force. Consistency is measured by means of a cone penetration test. See penetration (grease). The consistency of a grease depends on the viscosity of the base oil and the type and proportion of the thickener. It may also be affected by recent agitation; to take this phenomenon into consideration, a grease may be subjected to working (a standard churning process) prior to measuring its penetration value. See NLGI consistency grades.