Rachel Elnaugh became the first female investor on the original BBC series Dragons' Den panel.
Elnaugh was one of the original Dragons when the British programme launched in 2005. She was a businesswoman associated with Red Letter Days, the experience-gift company she co-founded, and brought experience in building and marketing consumer businesses to the panel. Her participation gave the first investor lineup a female Dragon before later additions expanded the panel's representation.
Deborah Meaden is often named in answers because she became one of the show's best-known long-serving Dragons, but she joined later, in 2006. Hilary Devey and Kelly Hoppen also appeared in later series. Elnaugh left after the first series, so she was not part of the programme's long-term panel even though she held the distinction of being its first female investor.