Definition of "three-lipped" []

• Having three lips (adjective)

WordNet. Princeton University. 2010.

• "- Internal side-cutting tool (boring tool) or spiral-fluted counterbore (three-lipped twist drill) to produce the hole with machining allowance for reaming."
• "Being a three-lipped tool, it is used for expanding holes (preparation) for reaming."
• "- three-lipped twist drill (spiral countersink) - head counterbore or counterboring tool with pilot"