1. noun /ˈsɪɡnəʧɚ/
A “signature” was placed on all things by God to indicate their affinities — but it was hidden, hence the search for arcane knowledge. Knowing was guessing and interpreting, not observing or demonstrating.
2. adjective /ˈsɪɡnəʧɚ/
Consider Las Fallas of Valencia, Spain, arguably the most signature of signature ephemera.
Wikipedia foundation.