As in phala फल - fruit (effect)
頗字門，入諸法遍不可得故
Kuamrajiva
入頗字門，悟一切法遍滿果報不可得故
Xuanzang
頗字門一切法不堅如聚沫故
Amoghavajra
PHA because no fruit (phala) is apprehended.
Conze
The syllable PHA [means] all mental phenomena are openings because of the non-attaining of fruit (phala).
Jayarava