(Of a task or undertaking) ineffectual; useless:remonstrating with him seems ever to have been a bootless task...
I wasted two weeks trying to redesign the front page, which was bootless; I ended up redoing it with new graphics which are nearly identical to the old.
After the bootless repair mission, Gnat napped and I worked.
But arguing with people who don't want to hear is fundamentally bootless.
Origin
Old Englishbōtlēas 'not able to be compensated for by payment' (see boot2, -less).