We don't have synonyms for week-long yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are seek, weak and reek.
(n) :
A period of seven days beginning with Sunday or Monday.
(n) :
A period of five days beginning with Monday.
(n) :
A subdivision of the month into longer periods of work days punctuated by shorter weekend periods of days for markets, rest, or religious observation such as a sabbath.
(n) :
(following a named day) A date seven days after (sometimes before) the specified day.
(n) :
A period of seven days beginning with Sunday or Monday.
(n) :
A period of five days beginning with Monday.
(n) :
A subdivision of the month into longer periods of work days punctuated by shorter weekend periods of days for markets, rest, or religious observation such as a sabbath.
(n) :
(following a named day) A date seven days after (sometimes before) the specified day.