Main Entry: oblig·a·to·ry

Pronunciation: \ə-ˈbli-gə-ˌtȯr-ē, ä- also ˈä-bli-gə-\

Function: adjective

Date: 15th century

1 : binding in law or conscience
2 : relating to or enforcing an obligation <a writ obligatory>
3 : mandatory, required <obligatory military service>; also : so commonplace as to be a convention, fashion, or cliché <the obligatory death scene in opera>
4 : obligate 1

— oblig·a·to·ri·ly \ə-ˌbli-gə-ˈtȯr-ə-lē, ä- also ˌä-bli-gə-\ adverb