2
general::
thrash sth out
[ M ] informal
to discuss a problem in detail until you reach an agreement or find a solution
• If we've got an important decision to make, we sometimes spend a whole day thrashing it out in a meeting.
Cambridge-Phrasal Verbs
3
general::
verb hit sb many times ADV. soundly That boy deserves to be soundly thrashed! PREP. with He thrashed the poor servant with his stick. move your arms and legs in an uncontrolled way ADV. helplessly, violently, wildly | about, around The cow fell on its side and thrashed about wildly. defeat sb easily in a game ADV. soundly The visiting side were soundly thrashed.
Oxford Collocations Dictionary