An example of something banal are boring knock-knock jokes that have been told many times before.
Origin of banalFrench ; from OFr, designating objects (such as ovens or mills) belonging to feudal serfs (hence common, ordinary) ; from ban, decree, legal control: see ban
Origin of banalFrench, from Old French, shared by tenants in a feudal jurisdiction, from ban, summons to military service, of Germanic origin; see bhā-2 in Indo-European roots.
(comparative banaler or more banal, superlative banalest or most banal)
From French banal, from Medieval Latin bannalis (“pertaining to compulsory feudal service, applied especially to mills, wells, ovens, etc., used in common by people of the lower classes, upon the command of a feudal superior; hence, common, commonplace”), from bannum (“command, proclamation”).