Na Yin Water of the Great Sea (大海水): the image of a pillar pair
Na Yin: Water of the Great Sea (大海水)
Na Yin assigns a poetic image to each consecutive pair of stem-branch combinations. "Water of the Great Sea" (Da Hai Shui) belongs to the pairs 壬戌 and 癸亥.
How Na Yin is used
Traditional readers use Na Yin as a texture layer — an image for the quality of a pillar pair — rather than as a prediction. Different schools weight it differently.
Where you can see it
Build a chart on MingLens to see the Na Yin of your year pillar and check whether "Water of the Great Sea" appears in your structure.
Boundary
Na Yin images are cultural vocabulary, not statements of fact about a person.