"GROOVY!" refers to a game mechanic in Mother 4. The player characters each have a meter associated with them, which fills up in combat. Upon the meter filling up all the way, the respective player character receives a GROOVY! bonus, allowing him or her to take an extra turn, even if it means interrupting an enemy's turn. The meter goes up when a player character deals damage (regardless of the amount dealt or number of enemies hit); for this reason, comboing is more effective for filling it. In contrast, it goes down when taking damage from an enemy or suffering a status effect. However, SMAAASH!! hits fill (and drain) the meter more. Additionally, eating food the player character likes fills the meter while eating food the player character hates drains the meter. Lastly, Travis's meter rises a great amount when successfully deflecting a projectile attack. This game mechanic is not present in the official Mother games.
- In the 70's, the word groovy is used as slang to describe something or someone as "cool", "neat", "great", etc.