Riffe

To riffle through life being generally confused and stressed over the harshness of life.

A select tune or Melody of a guitar tab in a song, like in AC/DC's "Back in black" the little tune that gets stuck in your head, is a RIFF

To make stuff up on the spot.
Can be applied to nearly anything--music, writing, lying, whatever.

Riff (verb, -riffed, -rif⋅fing. Informal): The art and science of making fun of low budget B-Movies by making snide and/or sarcastic comments (regarding the poor quality of the film's dialogue, acting, plot, shoddy film design, etc...) at the movie or television screen while the movie is running in the background. The comedy can be either high brow and esoteric or low brow and of the bodily branded humor.

West Midlands insult similar to chav. Origins are uncertain but it is thought to be an abbreviation of the phrase riff-raff, and localised use in Bromsgrove dates back as far as the late 1980s, if not earlier

Can be both a noun (riff), referring to the antisocial underclass, or an adjective (riffy), meaning something cheap, scummy or gully gully.

Riffing is not only a musical term rooted in Jazz but also a comedic term.

In common usage the term Jazz has not only several denotations but it also has several connotations: Jazz sometimes denotes an elaboration of something: To take something and elementally mix it up in such a way as to improve upon it.

"I bought an old car and jazzed it up."
"If you want to sell it, you'll need to jazz it up."
Jazz also has negative connotations:
"I slipped climbing into the truck and jazzed up my knee."
"The divorce jazzed up my whole life."

Say you had a Jazz quartet; a bass fiddle, a drummer, a sax, and a guitar. They can take a very old and very familiar tune and jazz it as a group to the point of being practically unrecognizable. Or, they do solo riffs on the melody. This is not a true solo, as, in turns, the musicians increase the volume of what they are playing while the others fade in volume and maintain the basic melody and beat. To riff then, is to touch upon a thing (in this case a melody) and depart from it to the point where it is unrecognizable by itself. Riffing is to touch lightly upon a thing only to depart from it.

Late-night talk show hosts and stand-up comics do topical or celebrity riffs. They may touch lightly upon an issue but quickly depart from it just for comic effect. They do not address or critique the issue or personality in question directly in a sober, mature or scholarly manner; instead they use it as a springboard to say something silly or irrelevant.

I got an email the other day containing an obviously doctored image of President Obama depicted as a Communist Witch Doctor. While the image visually riffs on his being of African heritage and a liberal politician, it does nothing to directly address his national health care policy proposals.

A segment of a song that puts emphasis on a certain instrument by using a distinctive sound. The instrument is usually a guitar.