Noun
chase; pursuit
アイドルのコンサート会場に、追っかけのファンがウジャウジャ集まっていた。At the pop star's concert the fans were swarming around the foot of the stage. chase scene (in a movie)
obsessive fan who follows a celebrity around; groupie
Noun, Adverb (fukushi)
in (quick) succession; soon (after)
Also written 追っ掛け【おっかけ】