The term 'It's an imposition' can be broken down into four crossword solutions: DUTY (4 letters), TAX (3 letters), PENALTY (7 letters), and LEVY (4 letters). DUTY is an obligation to do something, usually as part of a job or role. TAX is a fee imposed by a government on individuals or businesses. PENALTY is a punishment imposed for breaking a law or rule. LEVY is a TAX or charge imposed by a government or other authority. All of these words refer to a burden or responsibility that must be met.