Et la définition du "blockbuster" que tu te plais à poster est erronée, Dany. Comme le dit panda311, le terme (que ce soit au cinéma ou ailleurs, puisqu'il s'est répandu dans d'autres domaines) n'est pas à mettre en rapport direct avec son budget, mais bien avec les rentrées d'argent et les réactions auprès du public que le produit suscite.
"Blockbusters are entertainment products that are understood to generate interest and profits above and beyond similar products in the same time period. Originally associated with the financial performance of a stage play, a blockbuster today more often refers to a motion picture that attracts a great deal of attention and makes a great deal of money.
[...] One of the essential factors for any blockbuster is the amount of profits that the venture makes for the producers and owners of the work. In the case of a movie, a blockbuster is understood to generate profits of no less than $100,000,000.00 in United States currency. Generally, this figure must be earned within a relatively short period of time, such as a couple of months.
A second but less important trait of a blockbuster is an amount of enduring appeal. Even after the successful movie has completed a first run in the theaters, the property continues to be a moneymaker through video sales and Internet downloads. Over time, the blockbuster may eventually be regarded as a classic, due to the continued interest that is evidenced by succeeding generations through these sales.
Last, a true blockbuster often generates a strong reaction from movie critics. The reviews may be glowing or strongly condemning, but in all cases the finished product evokes a decisive reaction. In turn, the public may or may not agree with the assessment of the professional critics. Some blockbusters have been uniformly panned by critics, but enthusiastically embraced by the public."
Wikipédia, ce n'est pas une source d'informations fiable à 100%, surtout lorsqu'il s'agit d'obtenir la véritable signification d'un mot.