"penetrable" is a correct and usable word in written English.
It is an adjective that describes something that can be penetrated, entered, or crossed. For example, "This wall is not penetrable, so we cannot get through."
As you stumble into C.S. Lewis's Narnia, take note of the domed sky, penetrable by only immortals, where burning stars spell out premonitions and the actions of the world's creator, the famed lion Aslan; make fast friends with a wedded beaver couple; and, most importantly, stay clear of the evil White Witch, who has a special knack for making it "[a]lways winter and never Christmas".
The Canadian sculptor Robert Murray (1936– ) is notable among other artists working in the monumental stabile form; his lofty curved and folded aluminum sheets, while usually more geometric and less "penetrable" than the stabiles of Calder, nonetheless share the latter's paradoxical blend of lightness and substantiality, motion and stasis.
After the Wall had been transformed overnight from the Iron Curtain, penetrable only on pain of death, to a pile of graffiti-daubed rubble, picked over by souvenir hunters, the question was not whether European Communism was going to breathe its last, but when.
Even the world of art painting, though it is no less a victim than that of music to Appreciation rackets based on the concept of gilt-edged quality, is more penetrable to reason in this regard, since such values, or the pretenses about them advanced by investing collectors and museums, are more easily unmasked as efforts to influence market prices.
Given the fact that the underlying systems are so penetrable, it is relatively easy to fudge data — for example, to start out with three thousand votes for one guy and zero for the other before the counting even starts, even though the counter shows zero.
To the east, in Texas, agents are still struggling to stop persistent migrants in hundreds of miles of varying and penetrable terrain.
And the Caesar portrayed here by Jeffery Kissoon is definitely made of penetrable flesh.
For that we owe much to the Brazilian artist Hélio Oiticica (1937-80), who in the early 1960s initiated a series of artworks called "Penetrables" — essentially installations that physicalized color theory by allowing viewers to walk into, or through, monumental abstract paintings.
Two smaller "Penetrables" offer more concise, but almost as rewarding, experiences.
Any contemporary artist or curator proposing an "interactive" installation should take a close look at Oiticica's "Penetrables," which open up painting without closing off too many options.
Those led to his "Penetrables"—booths that could be entered and "Bólides," finely built wooden boxes with drawers or flaps that viewers could open to find various raw materials, mostly earthen.
