Coup: a sudden, violent, and illegal seizure of power from a government (Oxford Dictionary)
Coup: a change in government that is not in the nation's interest, when we decide that it's not, and not any sooner (United States government definition)
There is, of course, a formal definition likely somewhere buried in the government's glossary, but it's not quite relevant. It is clear in everyone's eyes that Egypt's change in government was a coup, whether or not the United States supported the change.
Since the overthrow, the United States has been on the "what do we do!?!" fence for what has seemed like an eternity. Formally labeling the change in government a coup leads to all sorts of ramifications, domestically and abroad. Namely, the US aid agreement with Egypt would likely be invalidated by the coup definition. This could complicate matters with the silent, but reciprocal aid given to Israel to avoid a perception of favoritism in the Middle East. Save for Afghanistan, Egypt and Israel are at the top of the list for United States military aid, and largely have been so since their 1979 peace treaty. At home, the government could be on the hook for the contracts that would terminate as a result of halting aid to Egypt - and the price is not cheap.
Quietly, over the past week, reports have leaked that aid to Egypt is not only under review, but may have already been suspended. Of course, this could be a technicality with a time lag - purchases already made for the fiscal year could be in the past and the looming cut so far in the future that it is still under discussion. Other funding tranches may simply not yet be due. Nonetheless, the positive side is sending a signal. The mess needs to be cleaned up and in an orderly fashion - not with civilians bleeding in the streets. Egypt may turn out, after all, to be a comparison against the change in regime in Iraq. What path is the one that leads toward a better future? Only time will tell.