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definiendum

[dih-fin-ee-en-duh m]
noun, plural de·fin·i·en·da [dih-fin-ee-en-duh] /dɪˌfɪn iˈɛn də/.
  1. something that is or is to be defined, especially the term at the head of a dictionary entry.
  2. Logic. an expression to be defined in terms of another expression previously defined.
Compare definiens.

Origin of definiendum

1870–75; < Latin dēfīniendum, neuter gerund of dēfīnīre; see define
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for definiendum

definiendum

noun plural -da (-də)
  1. something to be defined, esp the term or phrase to be accounted for in a dictionary entryCompare definiens

Word Origin for definiendum

Latin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012