Ishaq bin Yahya bin Talhah narrates from his paternal uncle Musa bin Talhah that Talhah slaughtered a camel and dug a well on the day of Dhu Qarad, then fed the people and gave them water to drink. So the Prophet (peace and blessings be upon him) said: "O Talhat al-Fayyad!" And so he came to be called Talhat al-Fayyad.
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 197