slowness

/ˈsloʊnəs/
noun
  1. The quality or state of moving, happening, or doing something at a low speed; lack of speed.
    • Her slowness in finishing the test meant she ran out of time.
    • The slowness of the old computer made it frustrating to use.
    • Drivers complained about the slowness of traffic during rush hour.
  2. The quality of taking a long time to understand or react; mental dullness.
    • The teacher was patient with the student's slowness in learning new math concepts.
    • His slowness in grasping the joke made everyone repeat it.
    • Slowness of thought can sometimes be mistaken for lack of intelligence.