Preventative
Part of speech: noun
Definition: Preventive (in all senses).
Part of speech: adjective
Definition: Preventive (in all senses).
Frustrating
Part of speech: verb
Definition: To disappoint or defeat; to vex by depriving of something expected or desired.
Part of speech: adjective
Definition: discouraging; causing annoyance or anger by excessive difficulty
Example sentence: I can't remember my dreams more than a couple of seconds after I wake up. It's frustrating because sometimes I dream that I'm watching a really good movie.