This is the 3560th most frequent Russian word.
сената
"Сената" is not a standard Russian word; it may be a misspelling or refer to "сенат" (senate), meaning a legislative or governing body.
In this context, 'сената' refers to the legislative body of government.
Сената обсуждает новые законы.
The Senate is discussing new laws.
Here, 'сената' is used possessively to specify members belonging to the Senate.
Члены сената проголосовали за принятие мер.
Members of the Senate voted to take measures.
In this case, 'сената' denotes the building or location associated with the Senate.