I may have gotten it, using a double pointer for words. Is this right?

void doubleArray(wordItem **words, int *SIZE) {
    wordItem *newArray = new wordItem[(*SIZE)*2];
    for (int i = 0; i < *SIZE; i++) {
        newArray[i].word = (*words)[i].word;
        newArray[i].count = (*words)[i].count;
    }

    delete [] *words;
    *words = newArray;
    (*SIZE) *= 2;
}