Final answer:
The space between adjacent columns in a colonnade is called intercolumniation.
Step-by-step explanation:
The space between adjacent columns in a colonnade, frequently determined by some multiple of the diameter of the column itself is called intercolumniation.
For example, if the diameter of a column is 1 meter and the intercolumniation is 2 times the diameter, then the space between adjacent columns would be 2 meters.
Intercolumniation plays an important role in the overall design and visual rhythm of a colonnade, creating a sense of grandeur and stability.