Synonyms of the word

satanic

• adj. Alternative form of Satanic (of, pertaining to or resembling Satan).
• adj. Evil, fiendish, devilish or diabolical.
• adj. Of or pertaining to any form of Satanism.

demonic

• adj. Pertaining to demons or evil spirits; demoniac.
• adj. Pertaining to dæmons in ancient Greek thought; concerning supernatural ‘genius’.

diabolic

• adj. Showing wickedness typical of a devil.
• adj. Extremely evil or cruel.

diabolical

• adj. Extremely wicked or cruel.
• adj. Of or concerning the devil; satanic.

evil

• adj. Intending to harm; malevolent.
• adj. Morally corrupt.
• adj. Unpleasant, as in 'an evil smell'.
• adj. Producing or threatening sorrow, distress, injury, or calamity; unpropitious; calamitous.
• adj. (obsolete) Having harmful qualities; not good; worthless or deleterious.
• adj. (computing, programming, slang) undesirable; harmful; bad practice.
• n. Moral badness; wickedness; malevolence; the forces or behaviors that are the opposite or enemy of good.
• n. Anything which impairs the happiness of a being or deprives a being of any good; anything which causes…
• n. (obsolete) A malady or disease; especially in the phrase king's evil (scrofula).

fiendish

• adj. Sinister; evil; conniving; like a fiend.

hellish

• adj. Causing pain, discomfort or distress.

infernal

• adj. Of or relating to hell, or the world of the dead; hellish.
• adj. (by extension) Of or relating to a fire or inferno.
• adj. Stygian, gloomy.
• adj. Diabolical or fiendish.
• adj. (as an expletive, not vulgar) Very annoying; damned.
• n. (obsolete) An inhabitant of the infernal regions.

unholy

• adj. Not holy; (by extension) evil, impure, or otherwise perverted.
• adj. Dreadful, terrible, or otherwise atrocious.