adj

• (archaic) Sane; in one's right mind.
  "He was not clever, poor fellow, he did not know what questions to ask; he asked the same questions again and again. He continued to show his own troubled thoughts, and the vague dread in his mind, […]"
• (of objects or actions) Showing mental quickness and resourcefulness.
  "This is a simple but clever trick to solve the problem."
• (of objects or actions) Showing inventiveness or originality; witty.
  "Mr. Woodhouse was almost as much interested in the business as the girls, and tried very often to recollect something worth their putting in. "So many clever riddles as there used to be when he was young--he wondered he could not remember them! but he hoped he should in time." And it always ended in "Kitty, a fair but frozen maid.""
• (UK, colloquial, chiefly in the negative) Fit and healthy; free from fatigue or illness.
  "But at that moment I knew it was all over for me, I had never thought that this day would come, but it had and I was not feeling too clever. In fact I had to escape to a nearby toilet to be sick."