rubber duck

Short definition from Wiktionary

Noun

1. 1
   A toy, made from rubber or rubber-like plastic, shaped like a duck; usually a floating bathtub toy.
2. 2
   An inflatable boat.

Verb

1. 1
   To act as a sounding board for a programmer that is debugging their code, facilitating rubber duck debugging.
2. 2
   Alternative form of rubber duck.