clock(s)-- a knitted design in a sock, found on the side "seams" of the sock (that is, in line with were the side seams would be on trousers, or a skirt, not up the front of sock, or at the back)

"...Well, you're driving like mad with this singular lad
(by the by, the ship's now a four-wheeler),
And you're playing round games, and he calls you bad names
when you tell him that "ties pay the dealer";
But this you can't stand, so you throw up your hand,
and you find you're as cold as an icicle,
In your shirt and your socks (the black silk with gold clocks),
crossing Salisbury Plain on a bicycle..."

--from The Nightmare Song, in Iolanthe

( and, paraphrasing Pooh-Bah, I desire to associate myself with those expressions of "welcome back"! )