v. phr. , informal 1. To chase or follow closely and without giving up. The Indians followed up the wounded buffalo until it fell dead. 2. Make (one action) more successful by doing something more. After Mary sent a letter to apply for a job, she followed it up by going to talk to the personnel manager. The doctor followed up Billy's operation with x-rays, and special exercises to make his foot stronger.
Compare: FOLLOW OUT, FOLLOW THROUGH 2 . 3a. To hunt for (more news about something that has already been in the newspapers, radio or TV news); find more about. The day after news of the fire at Brown's store, the newspaper sent a reporter to follow up Mr. Brown's future plans. 3b. To print or broadcast (more news about some happening that has been in the news before). The fire story was printed Monday, and Tuesday's paper followed it up by saying that Mr. Brown planned to build a bigger and better store at the same place.