linkage

noun

1. 1

   A mechanical device that connects things.

   “A linkage in my car's transmission is broken so I can't shift out of first gear.”

2. 2

   A connection or relation between things or ideas.

3. 3

   The property of genes of being inherited together.

4. 4

   A set of definitely related languages for which no proto-language can be derived, typically a group of languages within a family that have formed a sprachbund.