Lapwise

Despite their name, laptops seem to rarely be used lapwise.

Source: wiktionary

The man rushed through it just in time to leave beside the road a volcanic eruption that to have been the recipient of which, lapwise, would have made the trip memorable indeed.

Source: wiktionary

Thank goodness the cat took about half the coffee—which she certainly deserved. Things could have been a lot worse for me had she not been situated exactly where she was, lapwise, and anyway her hair grew back rather quickly.

Source: wiktionary

Reading postures varied. Some attendees sat cross-legged with a book resting lapwise. Others were curled up on a sofa.

Source: wiktionary