What it means
AといいBといい lists two representative aspects and states that the same evaluation applies to both. It often conveys “both A and B” or “whether one considers A or B,” with the repeated pattern emphasizing that neither aspect changes the speaker’s overall judgment. A and B are normally nouns, and the construction is especially common when describing qualities, features, or parts of something.
Usage note
Do not confuse this construction with といい meaning “it would be good to” or “you should.” Here, といい is repeated after two nouns and presents them as examples supporting one evaluation.
How to use it
この絵は色といい構図といい、見事です。
This painting is superb in both its colors and composition.
この絵は色といい構図といい、見事だ。
This painting is superb in both its colors and composition.
