Food for Thought
De- is the Latin prefix meaning "down" or "from." Combine this with pendere, "to hang," and you have a word picture that illustrates the meaning of dependable.
When a rock climber ties a rope around a rock and rappels off a cliff, his life "hangs from" the stability of that rock. Similarly, when a supplier makes a delivery on time, the projects depending on the delivery can continue. Dependability is keeping your word so that others can "hang" their plans on your promise.
De•pen•da•bil•i•ty n 1: quality of that which can be counted upon; able to be leaned upon 2: reliability 3: trustworthiness