1. superlative form of nitty; most full of or infested with nits (lice eggs)
Usage: informal; often used in the phrase 'nitty-gritty'
2. superlative form of nitty; most concerned with or dealing in small, detailed, or fundamental matters
Usage: informal; chiefly in the phrase 'nitty-gritty'

Examples

• Let's get down to the nittiest details of the contract.
• The nittiest part of the project involves checking every single line of code.
• After weeks of planning, we finally addressed the nittiest aspects of the proposal.
• She focused on the nittiest elements of the problem to find a real solution.
• The nittiest gritty of the situation became clear during the investigation.