Strong's 203 (ἀκροβυστία)

not circumcised, uncircumcised (with G2192 (ἔχω)), uncircumcision

the prepuce; by implication, an uncircumcised (i.e. gentile, figuratively, unregenerate) state or person

from G206 (ἄκρον) and probably a modified form of (the penis or male sexual organ);