Entry 1 sense Webster, 1913 Hydrocephalic /hīdˌ-rōs-ĕf-äl'-ĭk/ · Hy·dro·ce·phal·ic · IPA /hˌaɪdroʊsɛfˈɑlɪk/ 01 a. Relating to, or connected with, hydrocephalus, or dropsy of the brain. 1. Relating to, or connected with, hydrocephalus, or dropsy of the brain.