The answer to your question has been a subject of endless nerdy discussions for years. However I would answer it like this.

Rogue-like, loose definition: A defined genre of games, based on the classic game Rogue. Key features of such games are:

• dungeon crawling
• procedurally generated levels
• perma death
• turn-based gameplay
• grid-based movement

Rogue-like, strict definition: A defined genre of games, based on the classic game Rogue. Key features of such games are:

• dungeon crawling
• procedurally generated levels
• permadeath
• turn-based gameplay
• grid-based movement
• non modal (every action should be available to the player regardless of where they are in the game)
• complexity
• resource management
• hack and slash combat system
• exploration of areas and items
• typically such games are displayed in ASCII but it´s not a must

Roguelike, examples:

• Hack
• NetHack
• Ancient Domains of Mystery
• Moria
• Angband
• Tales of Maj'Eyal
• Dungeon Crawl Stone Soup

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Rogue-lite, definition: Not a defined genre at all but just an umbrella term for games from any genre that share at least some of the following characteristics:

• permadeath (a must have)
• procedurally generated levels
• metaprogression
• short to medium length runs with victory conditions (a run can usually be finished in one sitting)

Roguelite, examples

• FTL - Faster Than Light
• Dead Cells
• Nova Drift
• Hades
• Children of Morta
• Nuclear Throne
• Nova Drift
• Enter the Gungeon
• The Binding of Isaac