ˈ ̷ ̷ ̷ ̷ˌfēn noun
also iso·phane -ˌfān
( -s )
Etymology: isophene from is- + -phene (from Greek phainein to show); isophane International Scientific Vocabulary is- + -phane (from Greek phainein to show) — more at fancy
1. : a line on a map or chart connecting places within a region at which a particular biological phenomenon (as the flowering of a given plant) occurs at one time
2. : phenocontour