A particularly difficult question or puzzle.
Someone who, or something which, poses; a person who sets their body in a fixed position, such as for photography or painting.
A poseur; someone who affects some behaviour, style, attitude or other condition, often to impress or influence others.
Someone who asks a question or sets a problem.
A puzzling circumstance.
A difficulty that has to be resolved or dealt with.
A set of moves required to complete a climb.
A question to be answered, schoolwork exercise.
Objection.
Difficulty in accepting or understanding or refusal to accept or understand.
Causing a problem; problematic; troublesome.
Difficult to train or guide; unruly.