indeclinable

1. previously (lit. as cautioned) Vin.iv.44; Mil.48 (variant reading ˚kacca) usually as paṭigacc’ eva, e.g. Vin.i.342; DN.ii.118
2. providing for (the future), preparing for, with caution, cautiously Vin.ii.256; SN.i.57; SN.v.162; AN.ii.25; DN.ii.144; Thag.547; Ja.iii.208; Ja.iv.166 (in explⁿ of paṭikata & paṭikaroti); Ja.v.235.

so read for -gacca as given at all passages mentioned, see Trenckner Mil p.421, Geiger; Pr. § 38¹
ger fr. paṭikaroti (q.v.), cp. Sk pratikāra in same meaning “caution, remedy”