follow up (Noun) — A piece of work that exploits or builds on earlier work. ex. "his new software is a followup to the programs they started with"
follow up (Noun) — An activity that continues something that has already begun or that repeats something that has already been done.
follow up (Noun) — A subsequent examination of a patient for the purpose of monitoring earlier treatment.
follow up (Verb) — Pursue to a conclusion or bring to a successful issue. ex. "She followed up his recommendations with a written proposal"
follow up (Verb) — Increase the effectiveness or success of by further action. ex. "The doctor followed up the surgery with radiation"