engroove or ingroove /in-groovˈ/

1. To cut a groove or furrow in
2. To fit into a groove

• toughener
• tougheners
• toughening
• toughenings
• toughens
• tougher
• toughest
• tough going
• tough guy
• tough guys
• toughie
• toughies
• toughish
• tough it out
• tough love
• tough loves
• tough luck
• toughly
• tough-minded
• tough-mindedness
• toughness
• toughnesses
• tough out
• toughs
• touk