staunch

firme partidario

a very loyal and committed supporter

un partidario muy leal y comprometido

a very loyal and reliable ally

a firm and dedicated supporter of a cause or person

a very firm and determined opponent

someone with very strong conservative political views

defensa acérrima

a very strong and resolute defence

una defensa muy fuerte y resuelta

someone with a very strong and unwavering belief

someone with very strong socialist political views

negativa rotunda

a very firm and unwavering refusal

una negativa muy firme e inquebrantable

to stop or slow down the flow of blood from a wound

to stop or slow down the movement of a liquid