disincentive
Concise Oxford English Dictionary © 2008 Oxford University Press:
disincentive/dɪsɪnˈsentɪv/
▶noun a factor that discourages a particular action.
– derivatives
disincentivize (or disincentivise) verb.
disincentivize (or disincentivise) verb.
'disincentive' also found in these Oxford entries:

