TPS means transactions processing at any given sec. So, 10TPS would mean 10 transactions per second. Now, for Ethereum the transaction processing rate is 15-20 TPS for public blockchain, which is quite slow as compared to visa transaction handling i.e. 193 TPS (on an average) Slow transaction processing is the major reason why Ethereum is not scalable.
To eradicate such a problem, ethereum foundation is actively working on various procedures (like sharding) and other techniques. But this about the public blockchain. In private blockchain you have more control, over the number of miners, the bandwidth, the consensus model, difficulty, block processing time. So, you can do fairly well and squeezing in more TPS in a private blockchain