balls-out
Holding nothing back
Balls-out means with maximum effort, intensity, or speed—holding nothing back.
The term comes from mechanical governors where spinning balls fly outward at full throttle.
Despite the imagery, it's not anatomical: a balls-out performance, They went balls-out to finish on time.
The hyphenated form works as an adjective; without the hyphen, as an adverb.
At maximum power
- pedal-to-the-metalMaximum vehicular acceleration
- no-holds-barredWithout rules or restrictions
- wide-openFully extended or unrestricted
- unrestrainedNot held back
unrestricted · full-bore · hell-bent · breakneck · reckless · uninhibited · unbridled · uncompromising
full-throttle
At maximum power
- pedal-to-the-metalMaximum vehicular acceleration
- no-holds-barredWithout rules or restrictions
- wide-openFully extended or unrestricted
unrestrained · unrestricted · full-bore · hell-bent · breakneck · reckless · uninhibited · unbridled · uncompromising · relentless
bold
Courageous and daring
brazen · ballsy · courageous · intrepid · dauntless · unflinching · undaunted · plucky · spunky · nervy
balls-outhalf-hearted
Lacking sincerity or zeal
halfhearted · half-assed · lackadaisical · listless · tepid
balls-outcautious
Careful to avoid risk
restrained · careful · guarded · measured · prudent
balls-outtimid
Lacking courage or confidence
meek · cowardly · fainthearted · chickenshit · chicken