My daughter's name is
Delia, which we say with 3 syllables, (DEE-lee-uh), so
Cordelia would definitely be 4 in my book.
We do have a select few in our lives who pronounce my daughter's name more like DEEL-ya, 2 syllables. I prefer it with 3.
Point is,
Cordelia with 4 syllables, for sure.