Merriam-Webster Collegiate Dictionary - problem

 I. noun  Etymology: Middle English ~e, from Latin ~a, from Greek problema, literally, obstacle, from proballein to throw forward, from pro- forward + ballein to throw — more at pro-, devil  Date: 14th century  1.  a. a question raised for inquiry, consideration, or solution  b. a proposition in mathematics or physics stating something to be done  2.  a. an intricate unsettled question  b. a source of perplexity, distress, or vexation  c. difficulty in understanding or accepting I have a ~ with your saying that  Synonyms: see mystery  II. adjective  Date: 1894  1. dealing with a ~ of conduct or social relationship a ~ play  2. difficult to deal with a ~ child