An ELT Glossary : Fillers /Discourse markers

Fillers (sometimes called discourse markers) are words or sounds  like erm, er, you know, like, well, I mean  etc  used in spoken discourse to fulfil various functions. They may eg :

  • give the speaker thinking time while avoiding frequent or long pauses. Example : It was erm, like as if he wanted to tell us about it but, you know, wasn't sure what to say
  • serve as a turn taking strategy to indicate the speaker wants to take the floor. Example :  Erm - could I just add something? 
  • be used as a politeness strategy , indicating hesitation before giving a dispreferred second in an adjacency pair - ie a refusal of a request or invitation : Example A : Would you like to come to dinner on Saturday? B : Oh, erm well, I'd love to but ....