I came across this idiom in a title, in association with a noun:
[noun of a product category] — The need of the hour
What does this mean?
"Of the hour" is an expression used to indicate "of the present (short) period":
It doesn't literally mean an hour, but it does imply a short period of time.
Hour here just means a particular point in time. The need of the hour simply refers to some need at some point in time.
Its idiomatic mean " requirements at a given time" according to RPSC
Need of the hour has implication that it needs to be high priority.
Most essential need or requirement.
"need of the hour" refers to the most recent need or the most pressing need.