This is the 850th most frequent Dutch word.
oplopen
To incur, contract, increase, or rise.
In this context, 'oplopen' is referring to an increase or accumulation, often used in terms of damage, costs, or abstract quantities.
De schade aan de gevel liep snel op.
The damage to the facade increased quickly.
Here, 'oplopen' is employed to describe the act of acquiring or catching something, often used to refer to diseases or physical conditions.
Hij is een grote verkoudheid aan het oplopen.
He is catching a severe cold.
In this sentence, 'oplopen' is used to indicate an increase or rise, often in a significant or notable way, applied to a quantifiable measure such as price.