1. To combine things so that they are closely linked or so that they form one thing. English = integrate.
2. Of people, to mix people together who are from different social groups. Used especially when talking about different racial groups, or disadvantaged groups. English = integrate.
3. Of disabled people, especially deaf or hearing impaired people, to educate them within the normal school system, rather than in special schools. English = mainstream, integrate.
4. To combine two or more things into one thing. English = merge.
5. In mathematics, to perform the operation of integration. English = integrate.