9 examples of key
1
a watch key; a bed key; the winding key for a clock, etc.
2
the keys of a piano, an organ, an accordion, a computer keyboard, or of a typewriter.
3
the key of a line of defense; the key of a country; the key of a political situation
4
the key to a riddle; the key to a problem.
5
a telegraph key
6
he dominates play in the paint
7
an example that was fundamental to the argument
8
computers are fundamental to modern industrial structure
9
the central cause of the problem