Also known as: 煉乳, 練乳
Milk which has had its water removed until it develops a syrup-like viscosity. The general term "condensed milk" is usually considered synonymous in both America and Japan with "sweet condensed milk," which has significant amounts of sugar added to it.
In Japan, as in many parts of the world, sweet condensed milk is sold in squeeze bottles as a dessert topping. It's even a semi-popular topping for Shaved Ice.