(theater) Able to perform scripted material from memory, without need to refer to the text. / (accounting) Off the books, not officially recorded.

(colloquial, with regard to income) Undeclared for tax and social insurance etc.

(arachnology) A lamellate respiratory organ found in arachnids.

The Bible, or by extension the scripture of another religion.

plural of absey book

(obsolete) An ABC book; abecedary; a primer.

(publishing) A book that is marketed to a general audience (as opposed to books that have specialized audiences, such as academic books).

Alternative form of phrase book

Alternative spelling of off the books (preceding a noun only)

To alter financial records in order to commit fraud, tax evasion or theft.