Efficient and effective share the first three letters but shouldn’t be confused as their meanings are very different.
Efficient means ‘working well, without wasting time, money or energy’.
My new car is more fuel efficient than the old one was and saves me about £50 every week.
Laura’s the most efficient PA (personal assistant) I’ve ever had: my business life is perfectly organised with every little thing running smoothly.
Effective, on the other hand, means ‘successful, having the right effect or solving the problem’.
These painkillers aren’t cheap but they’re extremely effective – your headache will be gone in seconds.
A string of pearls would look very effective with that dress.
Now you know!