Difficult and Rarefied

Difficult adjective - Requiring considerable physical or mental effort.

Rarefied and difficult are semantically related. In some cases you can use "Rarefied" instead an adjective "Difficult".

Nearby Word: difficulty

Rarefied adjective - Of high moral or intellectual value; elevated in nature or style.

Difficult and rarefied are semantically related. Sometimes you can use "Difficult" instead an adjective "Rarefied".

Nearby Words: rarefy, rarefying