Roguetemple presents you a small and comprehensive list of several factors for evaluating the roguelikeness of a game; those may help you get an idea of what a roguelike is,
High Value Factors
Random Environment Generation
The game world and its contents are mostly procedurally generated with each game.
Permafailure (including Permadeath)
You must pay for your mistakes and choices, sometimes at the cost of life. Restoring games is discouraged and only provided to allow continuing split games.
Turn Based Interaction
All entities in the game world are queued in an endless loop and get their independant discrete turn to act.
Single command set
You can access all game commands from any place into the game. There are no artificial restrictions on what actions are available in a given game situation
Your game is not directly enrouted into a linear progression. You get to choose what you want to do, how and when
Middle Value Factors
You must research or find out the nature and usages of the items into the world.
You control a lone character
Lots of content
There are lots of monsters, items, locations.
Complex non-trivial world and object interactions
Items have non-trivial usages, you can do some things which may not be obvious for the item nature.
Low Value Factors
High ramped difficulty
The game gets hard very quick and you are very unlikely to win until you have acquired enough experience.
Monsters are players
The nature of the monsters is similar to the player, they can have equipment, player-like stats, artificial intelligence and are subject to the same world rules.
The player interacts with the world via a user interface based on character symbols that represent UI artifacts and entities into the world.
Hack and Slash
Gameplay involves around killing things and acquiring treasure