(Kangxi radical 37, +0, 3 strokes, cangjie input 大 (K), four-corner 40030 or 40800, composition or ⿸𠂇)

Ideogram (指事): a person with arms stretched out as far as possible, implying the meaning of big/great/large.

Compare also , which is a man with arms outstretched and a crest or tattoo on his chest, and to , which is a man with arms outstretched and leaning to side (running).

Pronunciation 2), the diphthong reading, is traditionally regarded as the correct one. However, the monophthong reading 1) has been recorded as early as Han Dynasty, and Sui-Tang rhyme books record both. Both readings are reflected in Sino-xenic readings in non-Sinitic languages, although the diphthong readings dominate in compounds. Axel Schüssler postulates that all pronunciations can eventually be traced back to liquid initials, i.e. 1,2) **laːts, 3) **hlaːts.

The three pronunciations are cognate. Within Chinese, they are cognate with (OC *tʰaːds, “too, excessively”), (OC *tʰaːds, “big”). Wang (1982) also lists (OC *l'aːnʔ, “big, magniloquent, ridiculous”) as a cognate, which Schuessler (2007) suggests is cognate with (OC *lan, *lans, “to extend”) instead. There are no unambiguous Tibeto-Burman cognates. Proto-Tibeto-Burman *taj (big), from which came Written Tibetan མཐེ་བོ (mthe bo, thumb), Anong tʰɛ (big; large; great), Mikir tʰè, ketʰè ("id."), Burmese တယ် (tai, very), is often compared with. There is no final –s in the Tibeto-Burman words, but a –y, which, according to James Matisoff, "indicates emergent quality in stative verbs". Also compare Chinese (OC *ʔl'aːl, “many, much”), (OC *taː, “all”).

This is often the first half two-character shorthand name of universities, for example 東大 (Tōdai, Tokyo University). Reading of first character often changes from kun'yomi to on'yomi.

: Hán Việt readings: đại ((đạc)(nại)(thiết))[1][2][3]
: Nôm readings: đại[1][2][3][4], đài[1][2], dãy[3][5], dảy[3], đẫy[3]