Definition of Moby Dick in US English:

Moby Dick

noun

  • Something likened to Moby Dick (the great white whale central to Herman Melville's novel), especially in being very large, important, or impressive.

Origin

1970s. From MobyDick, the name of the whale in Herman Melville's 1851 novel of the same name.

Pronunciation

Moby Dick

/ˌməʊbɪ ˈdɪk/