Definitions for "fluctuate"
To move as a wave; to roll hither and thither; to wave; to float backward and forward, as on waves; as, a fluctuating field of air.
To move now in one direction and now in another; to be wavering or unsteady; to be irresolute or undetermined; to vacillate.
To cause to move as a wave; to put in motion.
To change in price, value, or rate.
To change wildly from one reading or measurement to another.
To be continually changing or varying in an irregular way.
Keywords:  unstable, stock, downs, market, ups
be unstable; have ups and downs; "The stock market fluctuates"