Sloping or inclined; in a slanted or sloping position or direction.
From 'a-' plus 'slope,' where 'slope' comes from obsolete 'eslope' or possibly Middle English dialects meaning to slip away. The prefix 'a-' makes it specifically describe a state of being sloped.
This is one of the most logical and transparent of the 'a-' words, and it's almost surprising we stopped using it since 'aslope' is shorter and catchier than saying 'in a sloping manner.'
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