This is a metaphor, borrowed partly from the grazier's vocabulary, and partly from the arithmetician's vade-mecum.
The bow at that time was his vade-mecum; he never left it home.
Should prove a vade-mecum to Mining Engineers and all engaged in practical work.
It was her vade-mecum—good against rain, or sun, or mad bulls, or troublesome dogs.
Charles Alexander, the publisher of the vade-mecum, issued this magazine also.
Not a rambling, hap-hazard collection but a vade-mecum for youth from the ages of six or seven to sixteen or seventeen.
The passage in The Rhetorician's vade-mecum is the chief authority for their style.
This excellent handbook will prove a perfect vade-mecum to those engaged in the practical work of Mining and Metallurgy.
"a manual," 1620s, Latin, literally "go with me."