lacto-ovo-vegetarian UK /ˌlæk.təʊˌəʊ.vəʊˌvɛ.d͡ʒɪˈtɛəɹi.ən/US /ˌlæk.toʊˌoʊ.voʊˌvɛ.d͡ʒɪˈtɛɹi.ən/adjective 1noun 1forms 2 adjective1 •Describing such a person or diet. noun1 •A vegetarian whose diet excludes animal flesh, but accepts food that can be produced from a living animal without directly causing death (such as eggs, honey, and dairy products). formslacto-ovo vegetarians · lacto-ovo-vegetarians