Entry 1 sense Webster, 1913 Proteinaceous /prōtˌ-ĭn-āsh'-əs/ · Pro·te·i·na·ceous · IPA /prˌoʊtɪnˈeɪʃəs/ 01 a. Of or related to protein; albuminous; proteid. 1. Of or related to protein; albuminous; proteid.(Physiol. Chem.)