knallhart
Translation
rock-hard, tough, hard-core, uncompromising
Examples
Das Training war knallhart.
The training was hard-core.
Er ist ein knallharter Geschäftsmann.
He is a tough businessman.
Grammar Patterns
used as a predicative adjective The training was hard-core.
used as an attributive adjective He is a tough negotiator.
Similar Words
Synonyms: beinhart (bone-hard), unnachgiebig (unyielding); Antonyms: weich (soft), sanft (gentle)
Etymology
From 'Knall' (bang, crack) + 'hart' (hard). Literally 'bang-hard', suggesting something is so hard it would make a noise if you hit it.
Memory Tips
Imagine something so hard that if you dropped it, it would make a loud 'Knall!' (bang!).