The phrase "a sort of abstract" is correct and usable in written English.
It can be used when describing something that is not concrete or is a generalization of a concept or idea.
Example: "The painting is a sort of abstract representation of the artist's emotions during that period."
Alternatives: "a kind of abstraction" or "a type of abstract concept".
But it also occurs in a sort of abstract waiting room on the frontier of mortality.
"There's a sort of abstract relationship between our building and real boat construction," Mr. Maskin said.
Gravitas is a sort of abstract firepower that does not need to pull the trigger.
Dr. Jones prescribed me a straw and brocade loop, a sort of abstract bow, set to one side on an Alice band.
"They will be using animal imagery, puppets and shadow plays performed behind a screen to create a sort of abstract world.
(That, too, is something of an exaggeration, since politics has become a distinctly non-representational art, a sort of abstract painting of British society).
Graham showed decisively that the term li refers to an embedded contextual "pattern", rather than to any sort of abstract form or principle.
Sure, it's completely dust-proof (assuming all the ports are properly closed) and the 4-inch display is swathed in second generation Gorilla Glass, but it's all sort of abstract until you hold the thing in your hand the feel the urge to heave it somewhere.
Most comics — including, before this August, Tig Notaro — spend so many months honing their material that it becomes a sort of condensed abstract poetry.
"I had this idea of let's make the thing into a sort of weird, abstract spaceship or some adolescent fantasy of being in a spaceship".
Part of a series of wonderful, rarely seen drawings from this period, called "Parisian Abstractions," compose a sort of ABC of abstract forms that Noguchi quickly began to make his own.
