filioque
Filioque means "and [from] the son" in Latin, and it refers to the procession of the Holy Spirit. It was the diversive difference between the Roman and the Eastern Church and triggered, among other things, the Great Schism (1054): the Roman Church had added it to the Nicene Creed, but the Eastern Church never accepted the addition.

grand logariastes
A higher imperial official. the office was introduced by Alexios I Komnenos (1081-1118). The grand logariastes functioned as primary co-ordinator and controller of all fiscal services.

hypatos ton philosophon
(consul of the philosophers) Byzantine official and scholar responsible for the public schools of philosophy. The first one was Michael Psellos (11th C.), whose successors were John Italos and Theodore of Smyrna etc.

logothetes
A title designating high-rank officials, both administrative and ecclesiastical. Their responsibilities were mainly in the economic domain. The office of the logothetes of the Patriarchate gradually gained in importance after the 12th century. As for the logothetes of the metropolises, they seem to have assumed judicial jurisdiction.