1.Lit. [for farmland] to exist unplanted for a period of time. The fields lay fallow under the burning sun. It had been too wet to plant last spring.
2.Fig. [for a skill and talent] to remain unused and neglected. You should not let your talent lie fallow. Practice the piano before you forget how to play it.His writing had lain fallow for so long that he could hardly write a proper sentence.