Other forms: astonishing, astonished, astonishes
To astonish somebody is to surprise them very greatly indeed. Not a raised eyebrow — a stopped conversation.
It is a strong word and worth saving for strong occasions, since something that astonishes you leaves you briefly without a response. The passive is the commonest form, as in I was astonished to hear it. English keeps a scale here: surprised, amazed, astonished, astounded, each stronger than the last. The adjective astonishing is a genuine compliment, and the noun astonishment usually appears in the phrase to my astonishment.
1verbastonishTo surprise someone very greatly.
“The size of the bill astonished them both.”
Astonish grew an ending. The older word was astony or astun, to stun, and it was reshaped by the crowd of verbs finishing in ish: abolish, banish, cherish, establish.
Middle English
astoneyen
English, today
astonish
Built from
Probably an alteration (due to words ending in -ish: abolish, banish, cherish, establish, furnish, etc.) of earlier astony, astone, astun (“to astonish, stun”), from Middle English astoneyen, astonen (“to stun, astonish”), variant of stonen, stoneyen (“to stun, astonish”) prefixed with a-. However, compare Old French estonir, a rare variant of estoner (“to stun, astonish”).
Etymology from Wiktionary, CC BY-SA