WordNet sense 1 (an original model on which something is patterned):

archetype, pilot

WordNet sense 2 (an original creation (i.e., an audio recording) from which copies can be made):

master, master copy

WordNet sense 3 (of first rank or importance or value; direct and immediate rather than secondhand):

primary

WordNet sense 4 ((of a new kind or fashion) gratuitously new):

new

WordNet sense 5 (being or producing something like nothing done or experienced or created before):

innovative

WordNet sense 6 (containing seeds of later development):

seminal

WordNet sense 7 (original and of a kind not seen before):

fresh, novel

WordNet sense 8 (preceding all others in time or space or degree):

first

WordNet sense 9 (not derived; primary or simple):

underived