pester UK /ˈpɛstə(ɹ)/US /ˈpɛstɚ/verb 2noun 1forms 5 verb2 •To bother, harass, or annoy persistently.He pestered me with questions.She pestered him to help her. •(no longer used) To crowd together thickly. noun1 •A bother or nuisance.By now I presumed I had become a real pester. — 2017 formspestered · pestering · pestereth · pesters · pesterest