Overview
The "Lean" in Lean Startup traces directly to the lean manufacturing revolution developed by Taiichi Ohno and Shigeo Shingo at Toyota. Eric Ries has explicitly discussed Ohno's influence, describing "how Taiichi Ohno's ideas shaped the evolution of Lean Startup."
Specific Concepts Adapted
Waste elimination (muda): Lean manufacturing considers any expenditure of resources that does not create value for the end customer as waste. Ries translated this to startups: building features nobody wants is the ultimate waste. The MVP and validated learning are mechanisms to minimize this waste.
Small batches: Ries directly quotes Toyota: "Toyota discovered that small batches made their factories more efficient." He applied this to product development — ship the smallest possible increment, learn, and iterate rather than building large batches of features before testing. At IMVU, Ries deployed code to production nearly 50 times a day.
Andon cord / stop the line: Toyota's principle of stopping production when a quality defect is found. Ries adapted this as "stop the line so that the line never stops" — startups should halt and fix learning problems immediately rather than accumulating compounding errors.
Just-in-time production: Producing only what is needed, when it is needed. Translated to building only the features currently needed to test hypotheses.
Five Whys: Ries explicitly cites Ohno's root-cause analysis technique in "The Lean Startup" as a method for startups to diagnose problems systematically.
Continuous improvement (kaizen): The Build-Measure-Learn loop maps to the continuous improvement culture of TPS — each cycle produces learning that improves the next cycle.
Significance
The lean manufacturing lineage grounds the Lean Startup in a broader intellectual tradition of operational excellence. Ries did not merely borrow the word "lean" — he systematically adapted specific Toyota Production System concepts for the software startup context. This lineage also explains why the methodology resonated with large companies already familiar with lean manufacturing principles.
Sources: Wikipedia (Lean Startup), Lean Blog Podcast (Ries on Ohno), TechCrunch, Knowledge@Wharton