What does mac mean?
In informal British English, a mac is a raincoat, especially a waterproof or oilskin-style coat; it is a shortened form of mackintosh. The word sounds practical and everyday rather than formal, and many speakers now use raincoat or waterproof instead. In Scottish and broadly informal British speech, mac can also mean a male friend or buddy, often in direct address: “That’s my mac.” This sense comes from familiar forms of Scottish names and should not be confused with the garment term. Thus, the word’s usefulness lies in its compactness: one short form can evoke a weatherproof coat in one context and friendly social address in another. Because mac is informal and distinctly regional, neutral alternatives such as raincoat, friend, or mate are usually preferable in formal writing, though mac adds warmth and a recognisably British or Scottish flavour in conversation.
nounIn informal British English, a mac is a raincoat, especially a waterproof or oilskin-style coat. In Scottish and broadly informal British speech, it can also mean a male friend or familiar companion.
- An informal British term for a raincoat or waterproof coat.
- A Scottish and broadly informal British term for a male friend, buddy, or familiar companion.
"He pulled his old mac over his shoulders and set off through the rain."
"She put on her mac before stepping out into the drizzle."
"“Come along, mac,” said his friend as they headed to the match."
The standard plural is macs; the word is normally countable when referring to coats.
"The shop sells macs and other waterproof clothing."
“Mac” can mean a raincoat in the rain or a friend in a joke—four letters covering both British weather and banter.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does mac come from?
The raincoat sense developed in the early 20th century as a shortening of mackintosh, an early 19th-century term for an oilskin raincoat named after the Scottish surname Mackintosh. The Scottish sense meaning “friend” comes through Mac, a familiar form of names beginning with Mac- or Mc-, ultimately based on the Gaelic Mac, meaning “son of.” This development is separate from the shortening that produced the clothing term.
How mac is actually used
The raincoat sense is informal, somewhat dated in some regions, and less common in neutral writing than raincoat. The friend sense is especially associated with Scottish and working-class informal speech and may sound affectionate or teasing depending on context.
Easily confused with mac
A mackintosh is the full name for the raincoat, while mac is its shortened informal form.