— vigintillionth , adj.
/vuy'jin til"yeuhn/ , n. , pl. vigintillions , ( as after a numeral ) vigintillion , adj.
n.
1. a cardinal number represented in the U.S. by 1 followed by 63 zeros, and in Great Britain by 1 followed by 120 zeros.
adj.
2. amounting to one vigintillion in number.
[ 1900-05; vigint ( i ) twenty + -illion, as in million ]