Like the Japanese economy, the Japanese conversation has dwindled. Our words have lost their luxurious sheen, our sentences have been reduced to short strings of blah. We no longer need the metaphors of Osamu Dazai to convey our emotions, since a handful of familiar phrases have been encoded to cover most situations with ease.
Consider for example, the word yabai, first tossed around in the '50s by young chinpira (hoodlums) in Tokyo's back alleys. Back then, yabai meant "dangerous," clean and simple, and if you wanted to say something else then by golly you had to say it. But now yabai has evolved to refer to a whole slew of stuff, including "beautiful." It's become the one-size-fits-all adjective to describe anything from a desirous woman to delicious soba. A new video game, a rocky relationship, the events in Iraq -- these are all yabai. Shortened to yaba, it takes on comic dimensions. Lengthened to yabe, it's an indication of seriousness. Repeated "Yabai, yabai." it most often means the speaker is deeply (and happily) involved with something, like a new boy/girl friend, car or computer software. In this last case, "Yabai, yabai" is followed by another, recklessly abused phrase hamaru (addicted), as in "Yabai, yabai. Kuruma ni hamachatte (Oh man, I'm completely in love with my car)" -- which may strike you as bizarre, or just yabai.
For those of us suffering from bokyahin (lack of vocabulary), words like yabai are a godsend, but on the other hand, what's the use of learning an adjective when it could mean just about anything? The language is rife with such examples.