incidentaloma

noun, plural in·ci·dent·a·lo·mas, in·ci·dent·a·lo·ma·ta [in-si-den-tuh–loh-muh-tuh] /ˌɪn sɪˌdɛn təˈloʊ mə tə/.

1. an abnormal lesion or tumor detected by chance during a medical imaging test, physical examination, or surgery.