Definition: to speak to someone cruelly or angrily, criticising or scolding them. Often followed by “at” or “against”.
(This phrasal verb has more than one meaning)
E.g.1: I lashed out at Jenny and called her a “stupid idiot” and a lot of other names.
E.g.2: He took the opportunity to lash out against the company.
This phrasal verb cannot be separated.