Megan MacIntyre was a human who lived in Scotland in the 18th century. She was the wife of Seamus MacIntyre.

In 1746, when Megan was a teenager, English soldiers hanged her father and brother for being Scottish, raped Megan and left her for dead in the family's cabin. While fleeing their English pursuers, Seamus MacIntyre and the time-lost Montgomery Scott came upon the cabin. The three were trapped inside by the English officers, but were rescued by a band of Scottish soldiers and traveled to Inverness.

After the calamitous Battle of Culloden, Megan found Seamus and Scott, both wounded, and hid them in a cave. Seamus had a concussion but slowly recovered. Realizing he was dying, Scott made Seamus promise to return to his apprenticeship and make a life for himself and Megan.

Seamus and Megan MacIntyre had two sons and three daughters before Seamus died in 1803. They were direct ancestors of Frederick William Jeffries, the designer of the Jeffries tube. (TOS novel: Home is the Hunter)