The first rule about traveling between America and England aboard the Queen Mary 2, the flagship of the Cunard Line and the world’s largest ocean liner, is to never refer to your adventure as a cruise. You are, it is understood, making a crossing.

The second rule is to refrain, when speaking to those who travel frequently on Cunard’s ships, from calling them regulars. The term of art — it is best pronounced while approximating Maggie Smith’s cut-glass accent on Downton Abbey — is Cunardists.

The third rule, unspoken, is to not fling your champagne flutes into the roiling North Atlantic. My wife, Cree, broke this one. It was our second night aboard the ship. We were crossing, in January, from New York to Southampton. I was in black tie. She was in an extraordinary little black dress. We’d been flailing about, in the ship’s ballroom, to an adroit orchestra. We were happy, and tipsy.

We pushed open a door to the promenade deck. The icy wind heartlessly X-rayed us, but it was impossible to pull away from the railing. The North Atlantic in January is no joke; its heaving beauty is mesmerizing. It’s a volcano of sorts, one that seems to demand an offering. Better a champagne flute than to leap over the railing yourself.

This stemware-tossing impulse is, apparently, an old one. Evelyn Waugh, in his travel book Labels (1930), described being alone on a boat deck at night in the Mediterranean, champagne glass in hand.

“For no good reason that I can now think of,” he wrote, “I threw it out over the side, watched it hover for a moment in the air as it lost momentum and was caught by the wind, then saw it flutter and tumble into the swirl of water.”

Waugh added, “This gesture … has become oddly important to me.”

If travel makes you a bit reckless and sharpens your senses, being aboard the Queen Mary 2 in winter doubles this sense of intoxication. The churning ocean, splashing up the sides of the elegant dining room’s windows, two feet from your bottle of white burgundy and your tuna tartare, flips the switch on your survival instincts. You find yourself ravenous: eating a bit more; planning to stay out a bit later; dwelling a bit more upon sex.

What is it about ships (and trains and planes) and sex? We were left to ponder this question with fresh avidity after an unfamiliar QM2 waiter approached Cree early one afternoon while she was reading alone by a window in the ship’s pub.

This waiter, Cree reported later, was quite good looking, in a manner that resembled the actor Andy Garcia. He stood weirdly close.

He made small talk and ended by remarking, “If there’s anything I can do to make your trip more enjoyable, let me know.”

He walked away, then he strode back to Cree 15 seconds later and whispered, making eye contact, “Anything.”

This sotto voce invitation was a great gift to us — to Cree, to me, and to a friend, Will, who was traveling with us — because for the rest of the crossing we lasciviously uttered, at least hourly, what we decided should be the new Cunard motto: “Cunard. Anything.”

We boarded the QM2 at the Brooklyn Cruise Terminal in Red Hook on a Thursday, for what would be a seven-night passage to Southampton. The liner can easily complete this voyage in six days, but it slows down, like a power ballad, to save fuel and to extend its passengers’ enjoyment.