Terrell, also a former Amazon UK boss, will join the department store business on April 14 as managing director of John Lewis Direct. He will report to commercial director Phil Hullah.
Terrell has been at online lingerie retailer Figleaves for the last three years and was previously managing director of Amazon UK.
Terrell said: "This is a great brand committed to delivering the best multi-channel customer experience, and I am looking forward to being a part of making that happen."
Sales at John Lewis Direct were up 27% for the week to March 8, while store sales dropped 1.4%. A dip on Mother's Day hampered the final result of the weekly performance, despite the rest of the week being ahead. Unseasonable weather and Saturday's sporting events were also blamed for impacting sales.
Fashion was up 0.7% on last year, with strong performances in women's separates and outerwear and branded men's casualwear.