The headword, presumably extracted from the quotation given, is the present indicative middle/passive, third person singular, of the verb periptu/ssw, I enfold, enshroud, outflank, circle round; see generally LSJ s.v. [In her critical apparatus Adler notes that mss AF transmit the variant spelling *periptu/setai.] Cf. pi 1122.
[1] Syntacticum Laurentianum 56.12-3 lists both the lemma and the glossing verb as taking the accusative. Adler also cites Syntacticum Gudianum as identical.
[2] The glossing verb is the same form as the headword, but from the verb periba/llw, I throw round, throw about, encompass; cf. pi 1077, pi 1078, pi 1079, and see generally LSJ s.v.
[3] An approximation of Theophylact Simocatta, Histories 2.10.4 (Whitby and Whitby, pp. 56-7). The passage describes the return (winter 586 CE) of the Byzantine general Heraclius (the Elder, exarch of Africa 602-10, d. 610; PLRE IIIa s.v. Heraclius 3 and eta 466 (note)) into Roman territory near Theodosiopolis (Barrington Atlas map 89 grid D1) after pillaging large parts of Media (Barrington Atlas map 89 grid H2) during the Roman-Persian War of 572-591; Whitby p. 283-4. Philippicus (Philippikos, d. 614; PLRE IIIb s.v. Philippicus 3) was a Byzantine general and brother-in-law of the Emperor Maurice (mu 294); cf. phi 349, which mistakenly identifies him as Maurice's son-in-law.