adj. Concerned with trendy, liberal, or faddish causes, especially alarmist environmentalism and anti-capitalism. An activity or product is described as sustainable if it promotes a hippy agenda, regardless of whether the activity in question has any particular ability to be sustained over a long time period or not.
(Acronym: SAF) A term used to describe an aviation jet turbine fuel that meets the criteria of the Sustainable Aviation Fuel Users Group (SAFUG) and/or the Roundtable on Sustainable Biofuels. It is typically created from second generation biofuel feedstocks, such as algae.
"Sustainable Aviation Fuel is going to revolutionise the airline industry"
or
"SAF is a good investment"
A supreme form of architecture that the Internet needs to fucking talk about, involving buildings being littered with an earth shattering amount of plants.
Josh’s best friend just hit on his girl, so he decided to calm down by looking at pictures of sustainable architecture.