a factor causing trouble in achieving a positive result or tending to produce a negative result

tending to deter

try to prevent; show opposition to

(figurative) something that hinders or handicaps

something that hinders as if with bonds

(canon law) an impediment that invalidates a marriage (such as the existence of a prior marriage)

something that slows or delays progress

something immaterial that stands in the way and must be circumvented or surmounted