Block Height

1.

Number of blocks between the target block and the first block (genesis block). Each confirmation increases the block height by 1.

1.1 | Bitcoin (BTC)

The current block height of the Bitcoin (BTC) chain is in the 500,000s, with a new block being added roughly every 10 minutes and increasing the block height by 1.

1.2 | Activation

Activation of features or changes to the blockchain usually activate at specific block heights.
The block reward halvenings happen at pre-determined blockheights around 4 years apart
When BCH upgrades the features activate at pre-determined blockheights such that the network stays in sync.

2.

The total amount of blocks confirmed on a blockchain.

* All terms and definitions will change as the Cryptionary improves