[pvg]

Looking at the OED, usage as mould or shape for something, including printing is much earlier. In 1526 Tyndale apparently used it in his gospel translation - "Every man chylde that first openeth the matrix shalbe called holy to the lorde"†. It's a little misleading to say Sylvester 'coined' the term, he just used an existing term for his particular purpose.

† this also suggests William Tyndale possibly wrote the earliest Transformers fanfic.