archicerebrumZool.|ɑːkɪˈsɛrɪbrəm| [mod.L., f. archi- 2 + cerebrum.] The primitive brain of an insect or other arthropod. 1881[see syncerebrums.v. syn-].1882Athenæum 14 Jan. 60/2 In Apus the two pairs of antennæ are not supplied by nerves from the archi⁓cerebrum.