A person or animal that has dichromatic vision; someone with only two types of functional color receptors.
From Greek 'dicha' (two) and 'chroma' (color), plus the suffix '-at' (one who). This noun identifies individuals with the dichromasia condition.
Dogs are natural dichromats—they see the world in shades of blue and yellow, which means that red ball you think is so visible against green grass probably looks quite dark and hard to spot from their perspective.
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