Complex sentence: Due to ChapStick's popularity, the term has become a genericized trademark, used to refer to any lip balm contained in a lipstick-style tube and applied in the same manner as lipstick.
Split into simpler sentences: Due to ChapStick's popularity, the term has become a genericized trademark. It now refers to any lip balm contained in a lipstick-style tube and applied in the same manner as lipstick.