boo

Romantic partner — short for "Before Anyone Else." By the mid-2020s slightly millennial-coded but still in active use, especially in captions and texts. Gen Z is more likely to write "boo," "my person," or just the name.

The state of being fully locked into your relationship, acting couple-brained, and centering your significant other in basically every decision or vibe. Someone in boo mode is texting back immediately, mentioning their person constantly, declining plans because they'd rather stay in, and radiating that 'I'm taken and happy about it' energy. It's not toxic — it's just deeply couplified. Friends tend to notice when someone goes boo mode because it often means fewer group hangs and a new softness in someone's whole personality.

To start a romantic relationship with someone.

Describing someone who radiates soft, devoted, relationship-ready energy — the kind of person who seems built to be someone's person. Boo coded individuals are warm, attentive, low-drama, and have a vibe that screams 'I will remember your coffee order and check in when you're stressed.' It's a compliment flagging romantic potential and emotional availability. Not necessarily taken, but clearly the type. The boo coded person makes you feel cared for before anything official has even been established.