The state of being in direct contact or proximity with something. The contiguity of the two properties made it easy for the neighbors to communicate.
A sequential occurrence or proximity of two or more things, often leading to an association in the mind. The contiguity of the events in the story helped the readers understand the plot better.
In psychology, the principle that ideas, memories, or experiences occurring together in time or space tend to become associated. According to the law of contiguity, you are likely to recall the smell of popcorn when you see a movie theater.