This is a theory into the meaning about the Split Worm because of its similar appearance traits to that of male genitalia.
One of the general themes of Silent Hill 3 is around maternity and birth, therefore it could also slip into the region of sexual experiences.
It's possible then that the appearance of the Split Worm represents that of male genitalia; hence, possibly symbolising Heather Mason's first sexual experience (if it has ever occurred). What further backs this is that when the Split Worms hits Heather she makes a gasp for breath, as if she is fatigued after a sexual event that she seemed to endure.
|Silent Hill 3|
|Heather Mason - Douglas Cartland - Vincent Smith - Claudia Wolf - Leonard Wolf|
|Harry Mason - Alessa Gillespie - Stanley Coleman - Lisa Garland - Jennifer Carroll - Joseph Schreiber - James Sunderland - Robbie the Rabbit - Greys|
|Closer - Double Head - Glutton - Insane Cancer - Monster in Locker - Numb Body - Nurse - Pendulum - Scraper - Sewer Monster - Slurper - Valtiel|
|God - Leonard Wolf - Memory of Alessa -Missionary - Split Worm|
|Items - Worlds & Dimensions - Religion|
|Questions - Audio - Reference Materials|