der Schnürsenkel
shoelace
A ribbon or cord that is threaded through the eyelets of a shoe in order to tighten and tie it on the foot.
Dein Schnürsenkel ist offen, pass auf, dass du nicht hinfällst.
Your shoelace is untied; be careful you don't fall.

shoelace
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shoelace
A ribbon or cord that is threaded through the eyelets of a shoe in order to tighten and tie it on the foot.
Dein Schnürsenkel ist offen, pass auf, dass du nicht hinfällst.
Your shoelace is untied; be careful you don't fall.

The word consists of the stem of the verb 'schnüren' (to lace, to tie up) and the noun 'der Senkel' (an old term for a cord or ribbon). So a Schnürsenkel (shoelace) is literally a ribbon for lacing.
Die Schnürsenkel dieses Stiefels sind aus Leder.
The shoelaces of this boot are made of leather.
The most important verbs in connection with shoelaces are 'binden' or 'zubinden' (to tie) and 'aufmachen' (to untie/open). If they come undone by themselves, you say they 'sind aufgegangen' (have come undone).
Kannst du mir bitte die Schnürsenkel binden?
Can you please tie my shoelaces?
To point out to someone that their shoelaces are not tied, you say: 'Dein Schnürsenkel ist offen' (your shoelace is untied) or 'Deine Schnürsenkel sind offen' (your shoelaces are untied).
Vorsicht, dein Schnürsenkel ist offen! Du könntest stolpern.
Careful, your shoelace is untied! You could trip.
cord / string
'Schnur' and 'Schnürsenkel' both refer to long, flexible things that can be used to tie something. 'Schnur' is the more general word and can be used for many purposes, for example for packages, curtains, or in the garden. 'Schnürsenkel' is much more specific: it belongs to a shoe and is threaded through the eyelets so that the shoe fits securely. Learners may confuse the words because a Schnürsenkel looks like a Schnur. But not every Schnur is a Schnürsenkel; 'Schnürsenkel' is used only for shoes.

Vor dem Bus bindet Paul schnell seinen Schnürsenkel.
Before the bus arrives, Paul quickly ties his shoelace.
Wir spannen eine Schnur zwischen zwei Bäume, um die Wäsche aufzuhängen.
We stretch a cord between two trees to hang up the laundry.