Meaning : Having great power or force or potency or effect.
Example :
The most powerful government in western Europe.
His powerful arms.
A powerful bomb.
The horse's powerful kick.
Powerful drugs.
A powerful argument.
Lacking power.
powerlessMeaning : Strong enough to knock down or overwhelm.
Example :
A knock-down blow.
Synonyms : knock-down
Meaning : Displaying superhuman strength or power.
Example :
Herculean exertions.
Synonyms : herculean