palae·ich·thy·es \ˌ ̷ ̷ ̷ ̷ˈikthēˌēz\noun plural Usage: capitalized Etymology: New Latin, from pale- + Greek ichthyes, plural of ichthys fish — more at ichthus in some classifications: a subclass of fishes consisting of the elasmobranchs, ganoids, dipnoans, and crossopterygians • palae·ichthyic\| ̷ ̷ ̷ ̷+\adjective