Megillah Reading
Question
What if I miss a word of the Megilla reading?
Answer
Shalom!
Thank you for your question.
If one misses a single word, then the obligation to read/hear the Megillah was not fulfilled. As such, it is vital to concentrate on the reading and follow along from a Chumash.
It is interesting to note that there is a view that a woman’s obligation of Megillah is to “hear” the Megillah, not to read it. Some derive form here that the women’s obligation in terms of the Megilla is an act of pirsumei nisa (publicizing the miracle). According to this approach if a woman misses a word during the reading of the Megillah, she has still fulfilled her obligation. Nevertheless, the halacha is not in accordance with this view and a woman must hear every word of the reading just like men.
Therefore, everyone should follow along silently with a Chumash so that if one misses a word or two one can quickly read the missing word(s) and then continue hearing the rest of the reading from the Ba’al Korei. (as long as most of the megillah was heard from the ba'al koreh)
Source
OC 689:2; Mishna Berura 689:1, 690:48