three sisters

Short definition from Wiktionary

Noun

1. 1
   The combination of maize (corn), pole beans (Phaseolus vulgaris or climbing beans, string beans, etc.), and squash (i.e. pumpkin), especially when planted together in intertwined plantings.
2. 2
   The spirits or gods of corn, beans, and squash considered collectively.
3. 3
   Used other than figuratively or idiomatically: see three, sisters.

Proper noun

1. 1
   Synonym of Orion's Belt.