insist
v.v. to say something very firmly so that others understand you will not change your mind. You use this when you want to make sure someone does what you ask or believes what you say.
v. to demand something forcefully or state a fact maintainably in the face of doubt or opposition. Often used to express a firm requirement that leaves no room for refusal.
I must insist that you wear a seatbelt in my car.
Although the restaurant was fully booked, the manager continued to insist that they could find a table for the regular guests.
While the evidence against the suspect was substantial, his legal team continued to insist on his innocence throughout the entirety of the trial.
Partly from Middle French insister, from Latin īnsistere; and partly from a back-formation from insistence. Compare typologically from the same PIE root Bulgarian настоявам (nastojavam), Russian наста́ивать (nastáivatʹ).
The verb can be intransitive, but it often takes a 'that' clause or the preposition 'on' followed by a gerund or noun phrase.
she insisted to pay for dinnershe insisted on paying for dinnerThe verb 'insist' is followed by the preposition 'on' and a gerund, not an infinitive.