vade mecum
noun·/ˌvɑː.deɪ ˈmeɪ.kəm/
A handbook kept constantly at one's side, a trusted manual carried for ready consultation. A vade mecum travels with you, knowledge made companionable.
His vade mecum was dog-eared and penciled through, as if wisdom only counted once it had been handled.
Etymology
From Latin vade mecum "go with me," an imperative turned into a noun. The phrase is an invitation: let this book accompany your living.
Related Words
enchiridiona "in-the-hand" handbook; close kin
manualplain equivalent
compendiumcondensed reference; less portable in spirit
breviarycompact book, often devotional