1.an unsteady uneven gait
2.an unintentional but embarrassing blunder stumble v.
2.miss a step and fall or nearly fall
3.encounter by chance
4.make an error
air one`s dirty laundry/linen in public
to make public something embarrassing that should be a secret
The dinner party became uncomfortable when the host began to air his colleague's dirty laundry in public.
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