Is “Tighten” a Scrabble word?
Yes
TIGHTEN
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Tighten
/ˈtaɪ.tən/
verb
1.To make tighter.
“Please tighten that screw a quarter-turn.”
2.To become tighter.
“That joint is tightening as the wood dries.”
3.To make money harder to borrow or obtain.
“If the government doesn't tighten the money supply, inflation is certain to be harsh.”