The singular form is agendum. The plural forms are agenda or agendums.
"Agendum" is the singular form of the word. The plural form is "agenda."
Agendum is singular. Agenda or agendums is plural.
Agenda was previously the plural form of the original singular form "agendum".
Although agenda is the plural of agendum in Latin, in standard modern English it is a normal singular noun with a normal plural form (agendas).
The word agendum has become almost extinct. Originally agenda was the plural of agendum, meaning 'a thing to be done'. However, it became applied to a list of things to be done, and in this, the most usual modern sense, agenda has become firmly singular (replacing agendum), with the plural agendas. Compare with data.
Agenda
agenda
Something to be done; in the pl., a memorandum book., A church service; a ritual or liturgy. [In this sense, usually Agenda.]
An agendum is a single task which is to be achieved.
An agendum is a single task which is to be achieved.
Agenda. Although few people use the word agendum any more.
When changing a plural word with the ending "a" to a singular word, you would typically remove the "a" and the word may change to a different form altogether. For example, "agenda" changes to "agendum."