What does "limits reduction" provision mean?

"limits reduction" provision meaning in Insurance Dictionary

a phrase found in connection with uninsured and underinsured motorists (UM/UIM) protection to refer to restrict of insurance coverage terms that apply (in some says) to set out exactly how UM/UIM protection is suffering from the presence of other styles of coverage (age.g., auto medical repayments, employees settlement) that will use too. Under restrictions decrease, the restriction of insurance under UM/UIM is paid off by repayments from other types of insurance, as specified when you look at the applicable UM/UIM recommendation.