ἁπλότης haplotēs

From ἁπλοῦς: singleness, simplicity, or sincerity, without a folded or double motive. It is used of sincere service or a single heart (Eph 6:5; Col 3:22; 2 Cor 11:3). In contexts of giving, the same singleness is expressed as open-handed generosity or liberality (2 Cor 8:2; 9:11, 13). Rom 12:8 places ἐν ἁπλότητι with ὁ μεταδιδούς, the one who shares or gives. Both sincerity and generous openness are attested; which nuance the phrase takes there depends on that giving context, not on a separate theological sense of the noun.