Yes. You can add a narration to your withdrawals in two ways:
When adding a bank account:
The narration you add here becomes your default narration for all withdrawals to that account. Go to Wallet > Manage Accounts > Add Account to set it up.
When initiating a withdrawal:
You can add or change the narration at the time of withdrawal. This is optional. See: How Do I Withdraw From My NGN or GHS Wallet to My Bank?