Relating to or containing chlorophyll, used to describe organisms or compounds associated with the photosynthetic pigment.
From chlorophyll plus -an (relating to). This suffix appears in words like Arthurian (relating to King Arthur) and forms descriptive adjectives from root terms.
Chlorophyllan is essentially the adjectival form botanists use when they want to emphasize chlorophyll-dependent processes—you might read about 'chlorophyllan tissues' in a plant physiology paper, which instantly signals we're talking about the photosynthetic parts.
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