If you say that someone is indisposed, you mean that they are not available because they are ill, or for a reason that you do not want to reveal.
FORMAL adj usu v-link ADJ
The speaker was regrettably indisposed.
Translation English Cobuild Collins Dictionary
1 ailing, confined to bed, ill, laid up (informal) on the sick list (informal) poorly (informal) sick, under the weather, unwell
2 averse, disinclined, loath, reluctant, unwilling
1 fine, fit, hardy, healthy, sound, well
English Collins Dictionary - English synonyms & Thesaurus
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