ψαυστέον
From LSJ
τοῖς οἰκείοις βουλεύμασιν ἁλίσκεσθαι → hoist by one's own petard, hoist with one's own petard, hoist on one's own petard, hoisted by one's own petard, be hoist with one's own petard
English (LSJ)
A one must touch, Antyll. ap. Orib.10.23.23.
Greek (Liddell-Scott)
ψαυστέον: ῥημ. ἐπίθ., πρέπει τις νὰ ψαύσῃ, Ἄντυλλ. παρ’ Ὀρειβασ. 2. 436, Dar.