a logarithm
A logarithm is like a first-aid trick you use when someone trips on a log. You say, 'Here, take a log and use it to help you up.' It doesn’t actually help, but it sounds good.
'He fell on a log and I gave him another log to help him up.'
'Logarithm is like a log in the hand.'
'He tripped on a log and I gave him a log. He said it helped.'