Mention the word "soulmate" to a group of people and you're bound to get a few eye rolls. The idea that there's one magical person for you who you'll fall in love with instantly and never disagree with is just not realistic.

What does exist -- at least for many people -- is a person who you know instinctively, who you connect with on the deepest level and who allows you to grow as a person within the relationship. When that person is a romantic partner, you've come across something truly special.

So how do you know when you've found The One? Below, a team of love and relationship experts identify the most telling signs.

1. You communicate without speaking.

Soulmates can read each other like an open book. "They connect fervently on every level of being," clinical psychologist and relationship expert Dr. Carmen Harra told The Huffington Post. "One may finish the other's sentences, they may pick up the phone to call each other simultaneously, or feel like they simply can't be without their partner."

Dr. Sue Johnson, a clinical psychologist and author of Love Sense, said that a soulmate also knows how to respond to your emotional signals. "They stay close when you confide, give you their full attention and move in to answer to your needs, touching your hand when you are a little unsure, beaming and hugging you when you are glad, and tenderly comforting you when you are in pain," she added.

2. You know in your gut that you've found The One.

The old adage "When you know, you know" rings true when it comes to a soulmate connection. "There really is no guessing or wondering when the real thing comes along," wedding officiant and author Rev. Laurie Sue Brockway told The Huffington Post. "There is usually a telltale sign that lets you know when true love has arrived -– a voice in your head, a sense of recognition or a gut feeling that this is someone special to you."

3. The physical chemistry is palpable...

...and the electricity that you feel doesn't just happen on a sexual level. "Holding the hand of your soulmate throws your spirit into a whirlwind, even many years into the relationship," Harra said.

4. You've been totally comfortable around each other since day one.

Soulmates connect with ease right off the bat and let their true colors show without fear of judgment. "Soulmates often feel a sense of the familiar and a sense of comfort around each other," Brockway said. "Many people say it's easier to relax into that person and allow themselves to be vulnerable."

"It is the one who opens up to you –- who lets you in, so you can see them," Johnson added. "This is the kind of person who takes risks and shares about their inner world, their emotions and their needs."

5. But the relationship isn't all rainbows and butterflies. He or she challenges you like no one else can.

The soulmate relationship, despite what people might assume, isn't always smooth sailing. "A soulmate isn't always wrapped in the perfect package, physically or in terms of life circumstances -- nor does it mean that the relationship will come without challenge," author Kailen Rosenberg of matchmaking firm The Love Architects said. "Yet, the difference is that the life circumstances and the difficult challenges are a strengthening power that becomes the glue that keeps you together through the difficult times and helps each of you become your most authentic self."

What's more, we rely on our soulmates to help us evolve as people. "You might find a soulmate relationship to be rocky, and that your partner is someone who pushes your buttons and aggravates you at first because they bring with them some of the more difficult lessons for the soul," Brockway said.

6. You may not see eye-to-eye on every little thing, but you're on the same page where it really matters.

"A soulmate relationship doesn't necessarily mean both partners always share the same views, but that their overall goals and ambitions match," Harra said. "More diminutive opinions will differ, but soulmates generally have the same virtues and values and see the world through a similar lens."

7. The relationship brings both partners a sense of inner calm.

It's obvious when you're with the wrong person; you are insecure about the relationship and worry that one false move will turn your partner off. That's not the case for soulmates.

"You feel confident that your partner is with you for the long haul," dating expert Tracey Steinberg, author of Flirt For Fun & Meet The One said. "No matter what happens in your lives, you both agree that you are teammates and in it together." She continued, "Your inner voice tells you that you are in a healthy relationship. You trust each other, feel confident and comfortable around each other and feel safe discussing challenging topics in a mature way."

8. You and your partner have separate identities, but you face the world as one.

"Soulmates recognize that they are two parts of the same whole, and no outside influence or external matter can break that bond," Harra said.

9. You may have known each other for years, but you suddenly find yourselves ready for love at the same time.

When it comes to true love, timing is everything. "I have married so many couples who met in high school or in their twenties, maybe dated, broke up, moved on, or hung out around the same circle of friends and never connected," Brockway told The Huffington Post. "Then one day, they run into each other again, sometimes in magical ways, and love blooms." Keep an open mind and an open heart so that when your soulmate comes knocking, you're ready to answer the door.