Definition of be on (or on to) a loser in English:

be on (or on to) a loser

phrase

informal
  • Be involved in a course of action that is bound to fail.

    ‘you're on to a loser if you try and tell them what to do’
    • ‘But anyone who suggests starting a full-blooded cargo and passenger airport on the estate is on to a loser.’
    • ‘Of course, though, the announcer was on a loser from the outset.’
    • ‘We were on a loser from the moment the ingredients were ordered.’
    • ‘Remember that in court they would need to prove how they arrived at the cost of the charges and if they cannot do so, they would probably be on a loser with the courts.’
    • ‘When it became apparent that it was on a loser earlier this year, the company changed it policy on temps, effectively shutting the door on future claims.’
    • ‘A few years ago you would have been on a loser if you were trying to market products aimed at senior citizens on the web.’
    • ‘He was on a loser as they say…… the deal was already done in truth.’
    • ‘Even the defence council reckoned he was on a loser; he just hadn't been able to get any sense out of his client.’
    • ‘But, if he'd even toyed with the idea of defining journalism, he must have realised he would be on a loser.’
    • ‘I was on a loser until I asked him if he'd make the same decision if it were his health we were discussing.’