Lowered like a sailor given the wrong date? (6)
I believe the answer is:
abated
'lowered' is the definition.
(I've seen this before)
'sailor given the wrong date?' is the wordplay.
'sailor' becomes 'ab' (abbreviation for able seaman).
'given' means one lot of letters go next to another.
'the wrong' indicates anagramming the letters.
'date' with letters rearranged gives 'ated'.
'ab'+'ated'='ABATED'
'like a' is the link.
(Other definitions for abated that I've seen before include "reduced" , "weakened" , "Slackened off, died back" , "grew less" , "Subsided or decreased like storm" .)