(as) thin as a rail
Extremely skinny or slender. Have you seen Claire lately? She's become as thin as a rail in the last six months! I've always been thin as a rail, even when I try to pack on some muscle. I was thin as a rail after I returned from my service trip, so my mom insisted on making me home-cooked meals for a month.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.
thin as a rail
Very slender, as in I do not know why she's dieting; she's thin as a rail already. This simile, which uses rail in the sense of "a narrow bar," has largely replaced such other versions as thin as a lath or rake, although the latter is still common in Britain. [Second half of 1800s]
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.