lit. “going round” analysed by Bdhgh in 3 diff. meanings, viz. vāra (turn, course) desanā (instruction, presentation), and kāraṇa (cause reason, also case, matter), see DN-a.i.36 and cp. Kindred Sayings i.320.

1. arrangement, disposition, in phrase -ṃ karoti to arrange DN.i.179 (translation takes it literally “departure,” i.e. going out of one’s way, détour; or change of habit, see Dial i.245); MN.i.252, MN.i.326; MN.iii.7 MN.iii.62; SN.i.142 (trsl. “make occasion” [for coming]).
2. order, succession, turn, course (= vāra) DN.i.166 (˚bhatta i.e. feeding in turn or at regular intervals explained as vāra -bhatta Pp-a 232); MN.i.78, MN.i.282, MN.i.481; SN.ii.51 sq.; AN.ii.206; Ja.v.153 (= vāra); Pv-a.242 (aparā˚)
3. what goes on, way, habit, quality, property SN.i.146 (ceto˚; habits of mind, thoughts, but see also pariya); AN.v.160 (citta˚, see ceto).
4. discussion instruction, method (of teaching), discourse on (-˚) representation of (-˚) (= desanā); thus āditta˚ (of Vin.i.34) Dhp-a.i.88; esp. in cpd. dhamma˚; disquisition on the Dhamma DN.i.46; DN.ii.93; MN.i.83; MN.iii.67; SN.ii.74 SN.v.357; AN.iii.62; AN.iv.166, AN.iv.381; Snp.p.218; also in foll. vitakka˚ MN.i.122; deva˚ AN.iii.402 sq.; peta˚ Pv-a.92 cp. Vism.41 (˚kathā).
5. in Abhidhamma terminology specifically: pariyāyena, the mode of teaching in the Suttanta, ad hominem, discursively, applied method, illustrated discourse, figurative language as opposed to the abstract, general statements of Abhidhamma = nippariyāyena, nippariyāyato Vism.473 Vism.499; cp. Dhs-a.317 (figuratively).
6. mode, manner reason, cause, way (= kāraṇa) DN.i.185 (iminā ˚ena), DN.i.186 (id.); DN.ii.339 (ayaṃ p. yena ˚ena); DN-a.i.106 (tena tena ˚ena in some way or other); Dhs-a.366 (iminā ˚ena for this reason); esp. in phrase aneka -pariyāyena in many (or various) ways Vin.i.16, Vin.i.45; DN.i.1 (cp. DN-a.i.36), DN.i.174; MN.i.24; AN.i.56; Snp.p.15.
7. winding round (of a tree: branch), in doubtful reading at Ja.vi.528 (see pariyā)
   ■ See also nippariyāya.

fr. pari + i, cp. Class. Sk. paryāya in all meanings, already Vedic in meaning of “formula,” in liturgy, cp. below 4