Kind of. It means that the person making the offer already has the cash - if it’s a corporate/business purchase that cash may indeed come in the form of financing elsewhere, however the cash is already available so by definition isn’t secured by ownership of your property and so is not a “mortgage”. In a practical sense it likely means something like failing to make a repayment doesn’t automatically give possession of the property they bought.

All that said, in the Bay Area at least a cash offer from an individual means just that: the person buying it likely just sold a ton of stock, or their startup got bought, etc. I personally know people have done that (in some cases out of necessity: sellers favour short closing and no financing issues)