Do post #3842099 or post #3634129 qualify as sanpaku? I thought yes, but after seeing @yelite remove that tag from these posts and similar and asking them about it, it seems that term only applies when up to three parts of the eye are visible, and not when the iris is at the center of the eye for example.
How should we tag these eyes then? A lot of users use sanpaku that way - see for example post #3803206 - that's a popular character with commonly understood "sanpaku" eyes, but according to the literal definition the tag would not apply.
There's wide-eyed, but the name makes me think of the tag being associated with emotions (shock, fear, etc), not for when the character's iris is naturally small and the eye is not "wide open".