English

The crow's-foot notation indicates that an author can write several books, and a book can be written by several authors.

Noun

crow's foot ‎(plural crow's feet)

1. (chiefly in the plural) A small wrinkle in the corner of an eye, emblematic of aging.
   • c. 1380, Chaucer, Geoffrey, Troilus and Criseyde, volume two:

     So longe mote ye live, and alle proude,/Til crowes feet be growe under your eye

   • 1814, Austen, Jane, Mansfield Park, volume one, chapter XV, Thomas Egerton:

     You must get a brown gown, and a white apron, and a mob cap, and we must make you a few wrinkles, and a little of the crowsfoot at the corner of your eyes, and you will be a very proper, little old woman.

   • 2013 September 11, Kim Painter, “New wrinkle: Botox approved to treat crow's feet”, in USA Today:

     The Food and Drug Administration says it's an effective temporary treatment for crow's feet, the wrinkles that form next to aging eyes.

2. (sewing) A triangular embroidery stitch.
3. (databases) A symbol, resembling a bisected equilateral triangle, used in database diagrams to indicate plurality.
   • 1999, Robert J Muller, Database Design for Smarties

     The crow's-foot notation similarly represents relationships.

   • 2007, Geoff Coffey, Susan Prosser, Filemaker Pro 9: The Missing Manual‎

     Each crow's foot in your ER diagram indicates the need for a foreign key.

4. A caltrop.

Anagrams

• crowfoots