Amorphous (adjective): having no definite form.

“Across from the airport, just east of the Strip, the whole conglomeration like some strange amorphous triple junction, designed for tourists, or at least, for visitors: easy in and easy out.”

“Walk with Me” – David L Ulin

This word still doesn’t quite make sense to me as when I perceive something without form I conclude it is made out of a liquid or gas, something physical is hard for me to picture as not having a form.