plural of open letter

(intransitive, transitive) To open. / (intransitive) To reveal oneself; to share personal information about oneself; to become communicative. / (intransitive) To commence firing weapons.

A description, usually graphical, showing the major participants or components in a system and their interrelationships.

plural of open mind

present participle of lay open

(patent law, Japan and South Korea) To publish a patent for initial public review, prior to the formal application for registration. / (transitive) To expose or reveal (something).

(sports) An undefended goal. / An opportunity that is readily available.

(idiomatic) With enthusiasm, as if embracing

(business) A corporate officer of a corporation, company, or agency, responsible for executing decisions of the chief executive officer (CEO) according to their decided schedule; often initialised as COO.

(finance) A collective investment scheme which can issue and redeem shares at any time.