Definition of "two-lipped" []

• Having two lips. (adjective)
• Divided so that segments resemble the two lips when the mouth is more or less open; bilabiate. (adjective)

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• "These plants, which are mostly natives of mild climates of the old world, are characterized by having square stems; opposite, simple leaves and branches; and more or less two-lipped flowers which appear in the axils of the leaves, occasionally alone, but usually several together, forming little whorls, which often compose loose or compact spikes or racemes."
• "Sporangia clustered around the slender bristle, which is the prolongation of a vein, and surrounded by a vase-like, slightly two-lipped involucre."
• "From the flower often being two-lipped (see Fig.  120), the name of the order (_Labiatifloræ_) is derived."