etiolate (v), etiolation (n.)

Lack of light does several things to a plant. It will darken the leaves, it will lengthen them as the plant strives to make as much as it can with the little light it has. A stem with nodes will increase the distance between the nodes.

In this case, this Aechmea fasciata was grown inside under a skylight and the light was far too weak for normal growth. See the next picture to find one that is not etiolated.