Thania, you could have hundreds of definitions to that feeling...imagery what you have.

   Here are some: (depending of context, of course).

  -passé.

  -old fashioned.

  -hackneyed (batido...para assunto).

  -dull.

  -boring.

  -it´s no fun to do... (não tem graça, no sentido de ser chato...).

  -it´s no right to do...(não tem graça, no sentido "moral",ético; não é certo fazer isso...)

  -I don´t know what you see in him/it...(não sei que graça vc vê nele/nisso...)

   As you can see, I gave no "tight" definition, quite loose indeed; more aimed to make sense than to explain things just in a word.

   In all honesty, I hope this helps.

  PP.