Underpin/ˌʌndərˈpɪn/ Definition 1 of 2Pro Tip 1/3Emotional Strength Used to suggest something provides emotional support or confidence. His parents' unwavering belief underpins his ambitious pursuits. Pro Tip 2/3Not Literal Often metaphorical, not necessarily referring to physical support. Trust underpins a strong friendship. Pro Tip 3/3Business Context Frequently appears in business or economics to describe foundational concepts. Profitability underpins our business strategy.