difficulty

n. something that is difficult; hardship, trouble

A problem is an obstacle which makes it difficult to achieve a desired goal, objective or purpose. It refers to a situation, condition, or issue that is yet unresolved. In a broad sense, a problem exists when an individual becomes aware of a significant difference between what actually is and what is desired. Every problem asks for an answer or solution.
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Problem a question to which there is no obvious, immediate answer; a question that requires some work done on it before a solution can be available. [more]Difficulty - Community and Resources

Noun
1. an effort that is inconvenient; "I went to a lot of trouble"; "he won without any trouble"; "had difficulty walking"; "finished the test only with great difficulty"
(synonym) trouble
(hypernym) effort, elbow grease, exertion, travail, sweat
(hyponym) the devil
2. a factor causing trouble in achieving a positive result or tending to produce a negative result; "serious difficulties were encountered in obtaining a pure reagent"
(hypernym) cognitive factor
(hyponym) trouble, problem
3. a condition or state of affairs almost beyond one's ability to deal with and requiring great effort to bear or overcome; "grappling with financial difficulties"
(hypernym) condition, status
(hyponym) bitch
4. the quality of being difficult; "they agreed about the difficulty of the climb"
(synonym) difficultness
(antonym) ease, easiness, simplicity
(hypernym) quality
(hyponym) effortfulness
(attribute) difficult, hard

(n.)
The state of being difficult, or hard to do; hardness; arduousness; -- opposed to easiness or facility; as, the difficulty of a task or enterprise; a work of difficulty.
  

(n.)
Something difficult; a thing hard to do or to understand; that which occasions labor or perplexity, and requires skill and perseverance to overcome, solve, or achieve; a hard enterprise; an obstacle; an impediment; as, the difficulties of a science; difficulties in theology.
  

(n.)
Embarrassment of affairs, especially financial affairs; -- usually in the plural; as, to be in difficulties.
  

(n.)
A controversy; a falling out; a disagreement; an objection; a cavil.