Definitions of severe:

• adjective:   unsparing and uncompromising in discipline or judgment

  Example: "A parent severe to the pitch of hostility- H.G.Wells"

• adjective:   intensely or extremely bad or unpleasant in degree or quality

  Example: "Severe pain"

• adjective:   very bad in degree or extent

  Example: "A severe worldwide depression"

• adjective:   severely simple
• adjective:   very strong or vigorous

  Example: "A severe blow"

• adjective:   causing fear or anxiety by threatening great harm

  Example: "A severe case of pneumonia"

• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #17999)