Abstractionism is essentially the word used to describe the methods and ideas used to create abstract art.

It’s a bit of a broad category.

You can pee on a canvas, sculpt with tar, scream in gibberish or get paint on a snake and let it writhe around on a piece of artist’s paper — and you can say that all of the above are part and parcel to the work of abstractionism.  And, the most expert of abstract artists and critics would be hard-pressed to argue with you.

Consider the m-w.com definition:

Main Entry: ab·strac·tion·ism
Pronunciation: ab-’strak-sh&-”ni-z&m, &b-
Function: noun
: the principles or practice of creating abstract art

…and now, combine that definition with wikipedia’s page on abstract art (redirected from Abstractionism):

Abstract art is now generally understood to mean art that does not depict objects in the natural world, but instead uses color and form in a non-representational way.  In the very early 20th century, the term was more often used to describe art, such as Cubist and Futurist art, that depicts real forms in a simplified or rather reduced way—keeping only an allusion of the original natural subject. Such paintings were often claimed to capture something of the depicted objects’ immutable intrinsic qualities rather than its external appearance. (See abstraction.) The more precise terms, “non-figurative art,” “non-objective art,” and “non-representational art” avoid any possible ambiguity.

So, you might say that abstractionism is the freedom granted to artists to create art using any method that they see fit to use, towards any artistic end that suits their fancy.  In short, it’s the anything goes school of art.

Considering that, it’s no wonder that some people get turned off by abstractionism/abstract art.  Some people just don’t care much for freedom in general.  They like life by the lines, and expect others to think the same way they do.

Nanny-nanny-boo-boo, abstractionists say to them.  Let art be what the artist wants it to be, and the viewers be damned if they don’t like it.

Of course, this is also why some abstractionists find it very hard to make a living doing their art.

C’est la vie.