Not durable can mean flimsy, fragile, impermanent, temporary, or weak.
durable. look on dictionary.com for more synonyms.
abiding, long-lasting, stable, enduring
lasting, durable, patientintransientnot subject to variation through time
Synonyms for unbreakable: indestructible everlasting adamantine infrangible durable
long-lasting, enduring, tough, hard-wearing, strong, reliable, resistant, sturdy
synonyms - certain , constant , durable antonyms - unstable , weak , unsteady
They are synonyms.
Synonyms
Relative and kin are synonyms.
They are synonyms.
synonyms
The synonyms for upon is on