unsustainable

[ uhn-suh-stey-nuh-buh l ]
/ ˌʌn səˈsteɪ nə bəl /

adjective

not sustainable; not to be supported, maintained, upheld, or corroborated.

Origin of unsustainable

1670–80; un-1 + sustainable

OTHER WORDS FROM unsustainable

un·sus·tain·a·bly, adverb