A form worth repeating, held up as the thing to copy. The same word as patron - a pattern is what stands over the work as its example.
From Old French patron (a patron; also a model to be followed), from Latin patronus (protector, from pater, father); pattern and patron are literally the same word, because what a patron sets is exactly what is held up to be copied.
A form worth repeating, held up as the thing to copy — the same word, almost, as patron: what stands over the work as its example.