Spell-it-how-it-sounds version of "Psych."
"Sike" (or, more properly, "Psych") is a declaration that you just deliberately messed with someone's mind. Literally, "I fooled your brain."
"Psych" is a Greek root-word meaning "mind" - found in many other words, such as psychiatry, psychotic, psychic, psychedelic, etc., all of which relate to the mind. Note that the first syllable of all those words sounds like "sike."
The "Sike" spelling is most often used by people who have never read a book and are therefore only familiar with hearing the language spoken out loud rather than seeing it in written form.
Bill: I truly respect and value your opinion, man.
Ben: (hopefully) Really?
Bill: Sike!
Ben: (sobs)
Sike is a meaning of funny. You will get roasted so say SIKE NOOB!
Person: UR A NOOB
Other person: SIKE U ARE
A slang term typically used in Bangalore which basically means 'awesome'.
The new guy has sike basketball skills.
A slang word usually used in Bangalore, India which basically means "awesome"
Person A: I GOT THE JOB!!
Person B: THAT'S SIKE BRO!
Another word for “joking” but more professional.
But little did they know, the young lady was siking