When Miriam Silverman performed in “The Liar” at Shakespeare Theatre last year, her character Lucrece faced a man who compulsively lied through his teeth. But lies weren’t the only thing that shot through his teeth.

When his character sweetly proclaimed his love for her, actor Christian Conn spewed more than romantic platitudes.

“A big piece of spit flew into my eye,” Silverman says.

She was not flustered. She had spit on his face, too — and on the rest of the cast, as well.

“I don’t think there’s a leading man that has not been sprayed by me in performance,” she says. “During ‘All’s Well That Ends Well’ last year, I had a scene with Ted van Griethuysen. I would lean over Ted’s wheelchair and it would be an ocean of spray.”

(Alla Dreyvitser)

For theater actors, swapping spit isn’t a euphemism for kissing — it’s an exchange of bodily fluids that happens every night onstage, leaving no face unmoistened. Acting may be one of the only professions where it’s okay — even encouraged — to spit in your co-worker’s face. Spit is such a normal part of being an actor that it has developed its own backstage mythos, with actors reveling in being spat upon by a famous actor, or cracking jokes about aiming at inattentive audience members in the front row.

If you have never sat in a front row or seen theater in a tiny, black box space, you may have never noticed the spit. But move up — theatrical lighting will amplify the Shakespearean or Sondheimian spray.

Silverman’s worst spit moment came when she was doing a soliloquy in “Dog in the Manger.”

“I’m talking to the audience and I let a big glob of spit fall out of my mouth and onto my chin,” she says. “I’m supposed to keep talking, and I am thinking, Can people see the spit? Should I wipe it? Will I call more attention to it? That’s one of the dangers, that it’s a big amount. I don’t remember if I ended up wiping it.”

There are spitters, then there are sprayers. Spewers, even. Danny Scheie, currently playing Nero in “You, Nero” at Arena Stage, is one.

“Sometimes it’s running down their face,” he says of his tolerant co-stars. He’s careful to be courteous about it, citing a famous line in “A Midsummer Night’s Dream”: “And, most dear actors, eat no onions nor garlic, for we are to utter sweet breath.”

“I have a ritual. I floss. I have breath strips,” he says. “It’s gross enough — a nice shower of clean spit, you can’t complain about.”

(Alla Dreyvitser)

The works of Shakespeare, anecdotally, are known to produce more spit than that of other playwrights. The same goes for any play where an actor is expected to take on a foreign accent or speak in verse. It’s also bad news when an actor has to eat during a scene.

“You have to use a little more energy diction-wise, and it takes more vocal energy,” Silverman says. “You’re doing the same thing with your mouth when you’re chewing, it triggers the saliva glands to start producing, so I can only assume that’s what’s happening. It’s more aerobic in the mouth.”

Christopher Henley, one of the founders of the Washington Shakespeare Company, now with WSC Avant Bard, says any play can produce equal opportunities for spray.

“Really, any text (even the most contemporary and naturalistic dialogue), if it calls for tight rhythm, can cause one to focus primarily on picking up the cue and getting out the words clearly and cleanly and loudly, and to pay less attention to niceties such as swallowing sufficiently to keep from spraying,” he wrote in an e-mail.

He would know. He’s a spewer, reports Kari Ginsburg, his co-star in Avant Bard’s recent production of “The Mistorical Hystery of Henry (I)V.

“This is, I think, the fourth show that I’ve done with Christopher,” Ginsburg says. “He is a wonderful actor, and he has such an incredible voice, but you know you need to mentally prepare to wear a poncho. . . . You need to gird your loins and brace for impact. You can see the spit as it’s on its way across to you.”

(Given the chance to defend himself, Henley replied: “I would dispute that, if the evidence in support were not overwhelming. Which it is. I must own.”)

But spit reveals acting chops — at least that’s what actors tell each other.

“I think it’s a sign of talent and skill,” Scheie says. “It’s lubricating the voice. The more you have, the more healthy you are. The more extra liquid you have, the less you’re going to get hoarse.

“It’s like athletes sweating. It’s not gross; it’s a sign of you doing your job.”

The claim that better spitting makes better acting made its way into pop culture, as a plot point in one of the most-watched episodes of that ’90s chestnut “Friends.” In “The One With Chandler and Monica’s Wedding,” the character of aspiring actor Joey Tribbiani gets to be in a scene with an esteemed actor, Richard Crosby, played by the esteemed Gary Oldman. Joey is disgusted by how much spit Crosby produces as he delivers his lines, but Crosby explains that all real actors spit when they speak, leading to a massive spray-off. Oldman was nominated for an Emmy for the guest appearance.

Unfortunately, says Ellen O’Brien, voice and dialect coach for the Shakespeare Theatre, spit does not a better actor make. All it means is that there is more saliva in his or her mouth.

“But I do think you have to be willing to spit if that’s what it takes to get the language out,” she says. “You have to send sound forward, and that sends saliva forward.”

Still, some of the greatest stage actors in the history of the craft were known to spew. And being spat upon by a more famous star is a badge of honor among actors, an event to brag about for years to come. Jamie Foxx, er, gushed about being the target of Al Pacino’s wayward saliva in a speech honoring Pacino for his 2007 AFI Lifetime Achievement Award.

“We were doing a scene in ‘Any Given Sunday,’ and we were very close,” Foxx told the audience. “And I noticed wetness that was flying off of his lips, on my face. . . . As I sat there I said, ‘My goodness, this is the greatest actor in the world, but I need a squeegee.’

“And then it happened . . . a little bit of juiciness flew off of his mouth and landed on my lip,” Foxx said. “I tasted it. I brought it in, and I took that juiciness inside of me, I took that DNA, and the next thing you know, I won an Oscar.”

Scheie has been spat upon by Ian McKellen, and if he had the chance to do it again, he wouldn’t wash his clothes, he says.

“It was on New Year’s Eve, 1985, ‘The Cherry Orchard,’ ” Scheie says. “He was playing Lopakhin.”

Henley has never forgotten the time he was spat upon by British actor Anthony Quayle. Henley saw him in 1974 at the Kennedy Center, in a play called “The Headhunters” by Henry Denker.

“I was in the habit back then of buying the cheapest seat with a high school half-price discount (usually costing me a couple of bucks) and then moving to empty seats on the side front after intermission,” says Henley in an e-mail. After he was showered, he boasted to his actor friends.

Backstage, spit talk is hardly testy.

“We may tease each other if someone does it more,” Silverman says. “Maybe it’s a particularly wet night.”

“One of the cool things about actors is that you get really intimate,” Scheie says. “It’s a very quick bonding of relationships. We are very forgiving of each other. . . . In some ways we kind of love it. It’s a particular priesthood.”

Besides, as embarrassing as it can be for an actor when the audience notices his or her spit, it also serves as a reminder of what makes theater so special: In live performance, anything can happen.