Haraam
Haraam (Arabic: حَرَام ḥarām) is an Arabic term meaning "sinful". In Islam it is used to refer to any act that displeases Allah (God). Acts that are haraam are typically prohibited in religious texts and is the highest status of prohibition given to anything that would result in sin when a Muslim commits it. A milder ruling than haraam is "makruh", which means "disliked". A haraam (sin) is recorded by an angel on your left shoulder.
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