omo; OMO adjective used for signalling that a woman’s husband is not at home: oldmanoutUK OMO is an established branded soap powder.
As soon as a battalion was away over the water, all the singlies were straight over to check out the wives. Boxes of OMO appeared in the windows to advertise Old Man Out. I didn’t find it funny. None of the married blokes did. — Andy McNab, ImmediateAction, p. 51, 1995