Definition.com
40s (age) is a man's best years. after fifty a man begins to deteriorate, but in the forties he is at the maximum of his villainy.
Definition.com
40s (age) is when a man feels that he hasn't done what he intended, and that he hasn't got enough time left to do it.
Definition.com
40s (age) is a cut off point. The first 40 years give life text, the next thirty supply the commentary on it.
See also
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