Originally, decimate referred to killing one in ten. In modern English, it usually means destroying a large part of something.

“Very unique” can sound natural in everyday English, even though some editors prefer just “unique,” especially in formal writing.

“Earworm” comes from the German word Ohrwurm and describes a tune that seems to keep returning to your mind.

“Marijuana” is a rare case in English: the j is not said like j at all. Here is why, plus a simple contrast with typical English words.