Resource plant anatomy/lifecycle vocabulary
specifically development-focused

An Introduction to Plant Structure and Development by Beck looks comprehensive and has been well-reviewed. It has both photos and diagrams, and sections certainly deal specifically with growth/lifecycle. It's available to preview or purchase as an ebook on Google Play.

more general plant anatomy vocabulary resources

In print, Plant Identification Terminology: an illustrated glossary by Harris and Harris is a fairly standard reference, and I've found it very useful both for looking up terms and for just flipping through.

Online, but with fewer diagrams, you could try the Glossary page on the Angiosperm Phylogeny Website.

This might sound silly, but if you're looking for more of a course on the fundamentals rather than a dictionary of the specifics, the Botany Coloring Book is actually a great, seriously useful work.