Unsustainable

How to spell unsustainable

13 letters · 5 syllables

How to pronounce unsustainable

Say the part in capitals loudest.

What does unsustainable mean?

1. adjectiveNot able to be maintained or continued at the current rate or level.

Unsustainable in a sentence

• The company's spending was clearly unsustainable over the long term.

• Experts warned that the rate of fishing was unsustainable for the local stocks.

Where does unsustainable come from?

Language of origin: Latin

This word is built on the verb 'sustain', which English took from Old French 'sustenir' in the 1200s, itself from the Latin 'sustinere', meaning 'to hold up' or 'to keep going'. That Latin verb joins 'sub' (under, here softened to 'sus') with 'tenere' (to hold), so the literal sense is 'to hold from below', the way a foundation holds up a building. The same 'tenere' root quietly survives in a crowd of English words such as 'tenant', 'contain', and 'maintain', all of which involve holding in some way. The adjective 'sustainable' added the suffix '-able' (capable of being held up or kept going), and the negative prefix 'un-' produced 'unsustainable', meaning something that cannot be kept going. The term surged in modern environmental and economic writing during the late twentieth century. The spelling trap is the quiet middle: the 'ai' in 'tain' sounds like a plain long 'a', and the unstressed schwa endings invite a wrong vowel.

How the word is built

• un- (not)
• sus- (under, variant of sub-)
• tain (hold, from Latin tenere)
• -able (capable of being)