Sa2 [Idg. *so -- (m.), *sā -- (f.); nom. sg. to base *to -- of the oblique cases; cp. Sk. sa (saḥ), sā; Av. hō, hā; Gr. o(, h(; Goth. sa, sō; Ags. sē "the" (=that one); pe -- s=E. thi -- s] base of the nom. of the demonstr. pron. that, he, she. The form sg. m. sa is rare (e. g. Dh 142; Sn 89). According to Geiger (P.Gr. § 105) sa occurs in Sn 40 times, but so 124 times. In later Pāli sa is almost extinct. The final o of so is often changed into v before vowels, and a short vowel is lengthened after this v: svājja Sn 998=so ajja; svāhaŋ J i.167=so ahaŋ; svāyaŋ Vin i.2=so ayaŋ. The foll. vowel is dropped in so maŋ It 57=so imaŋ. -- A form se is Māgadhism for nt. acc. sg. taŋ, found e. g. at D ii.278, 279; M ii.254, 255, and in combn seyyathā, seyyathīdaŋ (for which taŋyathā Miln 1). An idiomatic use is that of so in meaning of "that (he or somebody)," e. g. "so vata . . . palipanno paraŋ palipannaŋ uddharissatī ti: n' etaŋ ṭhānaŋ vijjati" M i.45; cp. "sā 'haŋ dhammaŋ nâssosiŋ" that I did not hear the Dh. Vv 405. Or in the sense of a cond. (or causal) part. "if," or "once," e. g. sa kho so bhikkhu . . . upakkileso ti iti viditvā . . . upakkilesaŋ pajahati "once he has recognised . . ." M i.37. Cp. ya˚ ii.2 b. On correl. use with ya˚ (yo so etc.) see ya˚ ii.