An aspect of knowledge or its acquisition that is peculiar to the development of representations within a particular domain. The domain of number needs specific attention being paid to how numerous items happen to be, and specific counting skills have to be acquired. The domain of language needs attention to speech-sounds, and words have to be acquired.
See Domain (interactive), Domain (non-interactive), Domain (theory of mind), Double dissociation, Modularity, Representations (mental), Tiers