Architecturally speaking, an applied or engaged
column is a column that is halfway embedded in a wall.
This is a common motif in late 19th century architecture, used for regular division of horizontal wall space, and to break the monotony of many, many repeating window openings.
CrAzE has reminded me of some historical origins of the applied column: Ancient Egyptians used them on their dipylon temples, and the Romans did with psuedoperiteral edifices.