statement socks
n. A pair of socks chosen to make an impression, to stand out, or to express something about oneself.
Examples
2014
An added bonus: Statement socks are an easy and often inexpensive indulgence. Though high-end designs are certainly available (you can buy $185 socks at Barney’s, should your path in life lead to that), you can also buy the socks at stores like Forever 21 and Target, the latter of which says it "has seen a steady interest” in statement socks since introducing them in 2012.
—Megan Garber, “'Like Lingerie for Men': How Statement Socks Became So Trendy,” The Atlantic, October 01, 2014
2013
Well, this year’s interpretation (see, I’m becoming fashiony by osmosis) is to create a biker boot with strategically placed holes in the ankle, to either let the sweat out or give the wearer a whole extra layer of dressing anxiety as they rootle through their sock drawer for appropriately 'statement' socks.
—Lynne Barrett-Lee, “Join the tartan army? I'd rather have a naked foot…,” Wales Online, October 05, 2013
1996 (earliest)
Bolder spirits will reach for a graphic bravado tie, neon-bright T-shirt, colorful statement socks, snappy ankle boots.
—Catherine Fitzpatrick, “Making the cut toward elegance,” The Milwaukee Journal Sentinel, September 15, 1996