Function: transitive verb
Date: 1767
1 : to follow with something similar, related, or supplementary < following up his convictions with action ― G. P. Merrill>
2 : to maintain contact with (a person) so as to monitor the effects of earlier activities or treatments
3 : to pursue in an effort to take further action <the police are following up leads>
intransitive verb : to take appropriate action < follow up on complaints>