(orthography, typography) the Chinese character 大

cerebral cortex

the first of a family line (e.g. John I) / the first position in a succession (e.g. the first presidency) / the first person to hold such a position (e.g. the first president)

successive generations (often in reference to emperors)

original title (as opposed to a title of a translation)

deputy official / local official in the Edo period

a slide (item of play equipment)

subject of discussion, thesis (statement supported by arguments)

successive generations of a family etc. / (geology) eon

an order of merit higher than first class in the Japanese honors system