Russian ⇄ English Estonian Italian Latvian Polish Vietnamese

как обухом по голове stresses
gen.	be thunderstruck (e.g., he was thunderstruck – его как обухом по голове ударили Anglophile); slug; all of a heap; like a bolt from the blue (Anglophile)
Игорь Миг	stunning; mouth-dropping
idiom.	like a bolt out of the blue (He seemed to be very happy in his job, so his resignation came like a bolt out of the blue. Val_Ships); rude awakening (z484z); hit like a ton of bricks (тж. like a bolt from the blue Taras); sledgehammer blow (Bobrovska)
inf.	as a punch to the face (Technical)
proverb	sledgehammer blow

как обухом по голове: 11 phrases in 3 subjects

General	3
Idiomatic	2
Informal	6