Indians especially have a tendency to use the terms co-son-in-law and co-sister-in-law while referring to relations.
- The husband of one's wife's sister is called Co-son-in-law.
- The wife of one's husband's brother is called co-sister-in-law.
While introducing the relations to others they are called so.
The terms may be understood in the Indian sub-continent. But such terms are not understood by the native speakers.
I searched on the internet for the equivalent terms in English but I could not find them.
I here with attach two links so that you may understand what I mean:
What are the equivalent terms used by the native speakers while introducing them (the mentioned relatives) to others?