debt (n.)youdaoicibaDictYouDict[debt 词源字典]
late 13c., dette, from Old French dete, from Latin debitum "thing owed," neuter past participle of debere "to owe," originally, "keep something away from someone," from de- "away" (see de-) + habere "to have" (see habit (n.)). Restored spelling after c. 1400. In Middle English, debt of the body (mid-14c.) was "that which spouses owe to each other, sexual intercourse."[debt etymology, debt origin, 英语词源]
laugh (v.)youdaoicibaDictYouDict
late 14c., from Old English (Anglian) hlæhhan, earlier hlihhan, from Proto-Germanic *klakhjan (cognates: Old Norse hlæja, Danish le, Old Frisian hlakkia, Old Saxon hlahhian, Middle Dutch and Dutch lachen, Old High German hlahhan, German lachen, Gothic hlahjan), from PIE *kleg-, of imitative origin (compare Latin cachinnare "to laugh aloud," Sanskrit kakhati "laughs," Old Church Slavonic chochotati "laugh," Lithuanian klageti "to cackle," Greek kakhazein). Originally with a "hard" -gh- sound, as in Scottish loch; the spelling remained after the pronunciation shifted to "-f."
If I coveted nowe to avenge the injuries that you have done me, I myght laughe in my slyve. [John Daus, "Sleidanes Commentaries," 1560]
Related: Laughed; laughing.