A footnote term is a phrase or word used to refer to a source of information in the footnotes of a document. IDEM is a Latin term meaning 'the same' and is used to refer to the same source as the one previously cited. IBIDEM is also a Latin term meaning 'in the same place' and is used to refer to the same source as the one immediately preceding it. ETAL is an abbreviation of the Latin phrase et alii, meaning 'and others', and is used to refer to multiple authors of a single source.