The Collaborative International Dictionary
Unexpressible
Unexpressible \Un`ex*press"i*ble\, a.
Inexpressible.
--Tillotson. -- Un`ex*press"i*bly, adv.
Wiktionary
unexpressible
a. Impossible to express.
WordNet
unexpressible
adj. defying expression [syn: inexpressible] [ant: expressible]