The word idoneo in Italian is used to describe someone or something that is suitable, fit, appropriate or qualified for a given purpose. It derives from the Latin idonĕus of the same meaning.

Being an adjective, the -o ending changes in accordance with the gender and/or plurality of the subject it describes.
- il giorno idoneo = the suitable day
- la sede idonea = the suitable location
- i giorni idonei = the suitable days
- le sedi idonee = the suitable locations
Idoneo is usually followed by the prepositions a (to) or per (for) as in the following examples.
Il ragazzo è idoneo al servizio militare.
The young man is fit for military service.
Non è il momento idoneo per parlarne.
This isn’t the appropriate time to talk about it.

Some synonyms for idoneo are:
- capace = able
- adatto = suitable
- adeguato = adequate
- opportuno = opportune
- appropriato = appropriate