Phrasal verbs consists of a basic verb + another word or words. The two or three words that make up a phrasal verb form a short 'phrase' - which is why we call them 'phrasal verbs'.
thrash something out Fig.
to discuss something thoroughly and solve any problems.
The committee took hours to thrash the whole matter out.
A phrase that consists of a verb with a preposition or adverb or both, the meaning of which is different from the meaning of its separate parts.
A compilation of 50 phrasal verbs.