halfheartedly
In a weak way, without real effort or enthusiasm.
To do something halfheartedly means to do it without real effort, energy, or enthusiasm. When you complete a chore halfheartedly, you go through the motions but don't really care about doing it well. Maybe you're supposed to clean your room, so you shove things under the bed and call it done. Maybe you're practicing piano but your mind is somewhere else, and your fingers barely press the keys.
The word comes from the idea of giving only half your heart to something. Imagine your heart is split down the middle: you're keeping one half for yourself while offering just the other half to the task. That's not enough to do something well or meaningfully.
You can usually tell when someone is working halfheartedly. A halfhearted apology sounds empty and insincere. A halfhearted attempt at a sport means jogging slowly when you should be sprinting, or swinging weakly when you should be trying your hardest. Teachers notice when students complete assignments halfheartedly, turning in work that barely meets the minimum requirements.
The opposite is doing something wholeheartedly: putting your full effort and attention into it. When you care about something, whether it's a friendship, a project, or learning a new skill, halfhearted effort rarely leads anywhere worth going.