Bacteria develop “tolerance” if they become less affected by a biocide so that higher concentrations of the biocide are needed to stop them multiplying.
Source: GreenFacts
Bacteria - Bacterial resistance - Biocide(s)
GreenFacts Summary on Effects of Biocides on antibiotic resistance:
Deutsch: Toleranz gegenüber Bioziden
Español: Tolerancia a los biocidas
Français: La tolérance aux biocides