loose socks; baggy white socks
Specifically refers to the loose, often white, knee-high socks popular among Japanese schoolgirls in the 1990s and early 2000s. A wasei-eigo term derived from English 'loose socks'.
wasei-eigo (Japanese-coined English), from loose socks
In the 90s, loose socks were all the rage among high school girls.
She wore loose socks with her school uniform.