practicable
Able to be done for real with what you have.
Practicable means capable of being done or put into practice with the resources and circumstances you actually have. When something is practicable, it's genuinely workable in real life given what you have available.
If your teacher asks for a practicable solution to reduce cafeteria waste, she wants an idea that can actually be implemented at your school with existing resources and conditions. Installing solar panels might be wonderful in theory, but if your school has no budget for them, it's not practicable. Starting a composting bin or organizing students to sort recycling? Those might be practicable.
The word differs from possible, which just means something could happen. Building a treehouse might be possible, but if you have no tools, materials, or permission, it's not practicable. Engineers and project managers use this word because they need to distinguish between ideas that merely sound good and ideas that can truly be executed.
People sometimes confuse practicable with practical, but they're different. Practical means sensible or useful, while practicable specifically means doable. A plan might be practical (it makes sense) but not practicable (you lack what you need to actually do it).