stratospheric
[adjective]
Synonyms: excessive, dizzy, exorbitant, extravagant, immoderate, sky-high, steep, stiff, unconscionable, unmeasurable

[TahlilGaran] English Synonym Dictionary ▲

strat·o·spher·ic /ˌstrætəˈsferɪk◂ $ -ˈsfɪr-, -ˈsfer-/ adjective

1. [only before noun] relating to the outer part of the air surrounding the Earth

2. informal a stratospheric price, amount, level etc is extremely high or great:
stratospheric house prices

[TahlilGaran] Dictionary of Contemporary English ▲