immunotactoid /ˌɪmjunoʊˈtæktɔɪd/adjective 1noun 1forms 1 adjective1 •Of or relating to immunotactoids. noun1 •A tactoid of immune origin and formation, composed of immune complexes, monoclonal proteins, or both; such microscopic structures (described variously as microtubules, tubules, fibrils, or crystals) can interfere with glomerular function in the kidneys.immunotactoids seen on histopathology formsimmunotactoids