A portal of a subway tunnel.
A slope.
To bend or move (something) out of a given plane or direction, often the horizontal or vertical.
To tend to do or believe something, or move or be moved in a certain direction, away from a point of view, attitude, etc.
To slope.
To boil a liquid in a vessel having a reflux condenser
To flow back or return.
A technique, using a reflux condenser, allowing one to boil the contents of a vessel over an extended period.
The backwards flow of any fluid.
The leaking of stomach acid up into the oesophagus.