flabbergast
flab·ber·gast
verb
Origin
The origin of the verb is uncertain; possibly dialectal (Suffolk), from flabby or flap (“to strike”) + aghast. The word may be related to Scottish flabrigast (“to boast”) or flabrigastit (“worn out with exertion”). The noun is derived from the verb.
Related words
Word family
Broader terms
WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved. Wiktionary content is available under the Creative Commons Attribution-ShareAlike Licence.