The Collaborative International Dictionary
To be on all fours
All fours \All` fours"\ [formerly, All` four".] All four legs of a quadruped; or the two legs and two arms of a person.
To be on all fours, To go on all fours, or To run on all
fours (Fig.), to be on the same footing; to correspond
(with) exactly; to be alike in all the circumstances to be
considered. ``This example is on all fours with the
other.'' ``No simile can go on all fours.''
--Macaulay.
Usage examples of "to be on all fours".
I raised back up enough to be on all fours, so I didnt look like I was offering myself to him.
They could stand erect, maybe two meters or more tall, resting on that tail, but to walk or eat they needed to be on all fours.