something immaterial that interferes with or delays action or progress
"The sheer volume of paperwork required for approval acted as a major deterrent, slowing down our project timeline significantly."
Something that deters.
"The high speed limit acts as a strong deterrent to reckless driving on this stretch of highway."
Serving to deter, preventing something from happening.
"The high speed limits and frequent police patrols act as a strong deterrent against reckless driving in that neighborhood."