IPA: /ˈpækˌθrɛd/
KK: /ˈpækˌθrɛd/
A strong type of twine or thread used for sewing or tying packages and bundles together.
She used packthread to secure the boxes for shipping.
Packthread → The word is formed from "pack" (from Old English *pæcca*, meaning to bundle or wrap) and "thread" (from Old English *þræd*, meaning a thin strand). Together, these parts describe a thread used for bundling or packing materials together.
Think of 'bundling' ('pack') something with a 'thin strand' ('thread') — that's what packthread means.
No commonly confused words.