muchísimo / muchísima (adjective, adverb)

Frequency star
  1. very much, a great deal, a lot
  2. very much (as intensifier before nouns, meaning “a great deal of”)

Me duele muchísimo la espalda después de mudarme de casa.

My back hurts a lot after moving house.

Subir tantas escaleras siempre me cansa muchísimo.

Climbing so many stairs always tires me out a lot.

Me gusta muchísimo esta tarta de zanahoria, ¿inventaste la receta?

I really love this carrot cake you made, did you make up the recipe?