Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
tūtāmen, ĭnis, n. [1. tutor], a means of defence, defence, protection (poet. and postclass.): (lorica) decus et tutamen in armis, Verg. A. 5, 262.
Plur.: domorum aut vestium, Arn. 2, 71: deposcimus rebus fessis, id. 1, 15.