To make something conform to a standard or norm. The company is working to normalise its procedures across all branches.
To bring or return something to a normal or standard condition or state. The government is trying to normalise relations with the neighboring country.
To adjust data or a set of values to fit within a certain range or to have a mean of zero and a standard deviation of one. The data scientist had to normalise the dataset before running the analysis.
To cause something previously unusual or unacceptable to be regarded as normal or commonplace. Some critics argue that the film normalises violence for young audiences.