dot
dot the i's and cross the t's ensure that all details are correct. informal
join up the dots: seejoin.
on the dot exactly on time. informal
☞ The 'dot' referred to is that appearing on a clock face to mark the hour.
1998Oldie The Conditions of Sale state that the buyer has to pay the auctioneer on the dot.
the year dot a very long time ago. British informal
☞ The 'dot' probably represents a hypothetical number preceding 'one'.
2010Guardian Work out how much the City has earned for the UK since the year dot. Subtract the cost of the financial crisis. If you think the result is a negative number please book yourself on an evening class in remedial mathematics.