to dispute; to disagree; to argue opinionatedly; to wrangle

extreme and inflexible; fixated; stubborn in clinging to a notion; (psychology) paranoid

to execute (a plan); to grasp

receipt (written acknowledgement of receipt of an item)

to persist; to continue upholding; to persevere; to stick to sth; stubborn

rigid; inflexible

(literary) father's friends (of the same generation)

pedantic and stubborn

to choose what is good and hold fast to it (idiom)