Definition from Wiktionary, the free dictionary
- Unable to be exhausted; having an endless supply.
1830, Anna Maria Porter, The Barony, volume 3, page 460:
- The exhaustless conjecturings of that evening's full conversation, made such of the small party, as had hitherto been strangers, well acquainted with each other's turn of mind […]
- Of an automobile or similar machine, not producing exhaust; nonpolluting.