-blast. A suffix meaning an immature precursor cell of the type indicated by the preceding word. [G. blastos, germ]. immature precursor cell type; the cell type is denoted by the preceding syllables, e.g. osteoblast.
(plural defining moments) A moment in time that defines something, such as a person's success or failure, achievement or demise, talent, etc. A point at which the essential nature or character of a person, group, etc., is revealed or identified.
Confidence votes 70. A moment can be anywhere from a few seconds, up to a minute. Generally, a moment is defined as a point in time lasting from 1-3 seconds. In Old English, a moment was an exact measurement of time being 1.5 seconds or 1/40th of one minute.