the act of suppressing.

the state of being suppressed.

Psychoanalysis . conscious inhibition of an impulse.

Botany . the absence of parts normally or usually present due to the action of frost, disease, or insects.

Radio, Electronics . the elimination of a component of a varying emission, as the elimination of a frequency or group of frequencies from a signal.

Electricity . the reduction or elimination of irregular current oscillations or frequencies in a circuit.

noun

clampdown , crackdown , repression