Googolduplex

She was bigger than any exaggeration of most feet, more than a million, gazillion, googolduplex, […] more than much, much more than all fathoms, feet, miles, or anything anything.

From a googolduplex you can leap to a googoltriplex, a one followed by a googolduplex zeroes, and then to a googolquadruplex, which has a googoltriplex zeroes, and so on.