Multiple realities
(covers information from several alternate timelines)
"That'd be so noble "Pointy" if you weren't also throwing me under the bus!"
"'Pointy'? Is that a degoratory reference to –"
– James T. Kirk, Spock, and Christopher Pike, 2259 (Star Trek Into Darkness)

"Pointy" was an insulting nickname for some Vulcans. It was used to describe Ambassador Soval by Jonathan Archer when he was a young boy. When he used the term in 2121, his father told him not to call Soval that. (ENT: "Broken Bow")

In 2259 of the alternate reality, James T. Kirk angrily called Commander Spock "pointy" when he provided Admiral Christopher Pike with a detailed report of a mission in which the USS Enterprise had visited Nibiru but had violated the Prime Directive there. In reply, Spock said, "'Pointy'? Is that a derogatory reference to..." before he was cut off by Pike. (Star Trek Into Darkness)

Though never said, it is implied that this refers to a Vulcan's ears. Both B'Elanna Torres and Neelix have used this adjective, referring to Tuvok as having "pointy little ears" once each. Krem also referred to T'Pol as being "the one with the pointy ears" aboard Enterprise NX-01.