Ꝥ (minuscule: ꝥ), or Þ (thorn) with stroke was a scribal abbreviation common in the Middle Ages. It was used for Old English: þæt (Modern English "that"), as well as Old Norse: þor-, the -þan/-ðan in síðan,^[1] þat, þæt, and þess. In Old English texts, the stroke tended to be more slanted, while in Old Norse texts it was straight. In Middle English times, the ascender of the þ was reduced (making it similar to the Old English letter Wynn, ƿ), which caused the thorn with stroke abbreviation ( ) to be replaced with a thorn with a small t above the letter ( ).

Unicode encodes Ꝥ as U+A764 Ꝥ LATIN CAPITAL LETTER THORN WITH STROKE, and ꝥ at U+A765 ꝥ LATIN SMALL LETTER THORN WITH STROKE.

A thorn with a stroke on the descender also exists, used historically as an abbreviation for the word "through".^[2] The codepoints are U+A766 Ꝧ LATIN CAPITAL LETTER THORN WITH STROKE THROUGH DESCENDER, and U+A767 ꝧ LATIN SMALL LETTER THORN WITH STROKE THROUGH DESCENDER.