Definition of 'Debit Spread'
Two options with different market prices that an investor trades on the same underlying security. The higher priced option is purchased and the lower premium option is sold - both at the same time. The higher the debit spread, the greater the initial cash outflow the investor will incur on the transaction.
Investopedia explains 'Debit Spread'
For example, assume that there is a investor holding a call option who sells it for $2.50. Immediately following this sale, the investor buys another call option on the same underlying security for $2.65. The debit spread is $0.15, which results in a loss of $15 ($0.15 * 100).
Although there is an initial loss on the transaction, the investor is betting that there will be a significant change in the price of the underlying security, making the purchased option more valuable in the future.