I found this post a bit confusing and probably misleading too.

1) ==Dictionary.com: อ่าน ”extraneous” = “ik-STREY-nee-uhs”== This is definitely ‘American pronunciation. English would say “ik-STRAH-nee-uhs”. The difference should be mentioned.

2) ==…ให้ความหมาย “intrinsic” ว่าเป็น “คำใกล้เป็นคำพ้องของ ‘extraneous’”
โดยให้ความหมายพื้นฐานว่า “belonging to something by its very nature.”…== This is confusing.

“intrinsic” = belonging to something by its very nature; core (information/property)BUT “extraneous” = not belonging to that in which it is contained; OUTSIDE (information); not essential; not relevant to the matter under consideration.

So ‘intrinsic’ is very much opposite in meaning; an antonym of ‘extraneous’ (not คำพ้อง).