Lewis Short
(verb) : ex-signo (exign-), āvi, ātum, 1
* To write out, note down, record (very rare): omnia istaec quae tu dixti, scio, vel exsignavero,I could write it down exactly,Plaut. Trin. 3, 2, 29: pontifici sacra omnia exscripta exsignataque attribuit,Liv. 1, 20, 5.
Charlton T. Lewis, Charles Short, A Latin Dictionary