Save Gender Masculine Usage Dutch (Rare), Flemish (Rare) Pronounced Pron. EE-see-dawr, EE-see-do:r [key] Meaning & History Dutch form of Isidore. Known bearers of this name include Belgian author Isidoor Teirlinck (1851-1934), Belgian athlete Isidoor Van de Wiele (1924-2010) and Belgian cyclist Isidoor De Ryck (1926-2009).