Kolinahr
Kolinahr (ko-li-naar), as a word, described both the Vulcan ritual by which all remaining vestigial emotions were demonstrated as purged, and the mental discipline whereby this state was subsequently maintained. Not all Vulcans were required to make this final journey to pure logic. The duration of Kolinahr training was quasi-monastic in nature, and could vary from two to six (or more) years. (; ; )

T'Klaas, a student of Surak, was one of the first Kolinahr masters. His mummified remains were kept in the catacombs of the T'Karath Sanctuary, but were not marked. ()

The Vulcan monastery at P'Jem was a remote  for kolinahr and peaceful meditation. According to Sub-commander T'Pol, visitors would be turned away during the time of kolinahr. ()

In 2258 in the alternate reality,  discussed the Kolinahr ritual with  shortly before making the decision to enter Starfleet instead of the Vulcan Science Academy. He wanted to ensure that if he decided to undergo Kolinahr, she would not interpret his decision as a rejection of her, or his Human half. She lovingly reassured him that, regardless of the decision he made, she would proudly stand behind him. ()

In 2259, Spock briefly discussed Kolinahr with  (who at the time was impersonating humanitarian Doctor Aspen). Aspen admitted to never really understanding the point of Kolinahr; that since Vulcans naturally had emotions, why try to erase them? Spock responded that Kolinahr offered clarity and the ability to see oneself without bias, and admitted to be looking forward to his. ()

Spock began the process of the Kolinahr ritual after retiring from Starfleet circa 2270. By the end of his 2270s stay on , Spock had completed all but the final ritual of the Kolinahr, but failed to do so after receiving powerful telepathic signals from the V'ger entity in deep space, and experiencing strong emotions as a result. 

When discussing this with James T. Kirk and Leonard McCoy, the doctor mispronounced it as "kolineer". () 

In 2298, Tuvok began immersing himself in Kolinahr after resigning from Starfleet. Six years later, he entered into Pon farr and married . After they chose to raise a family, Tuvok postponed his studies. ()

When Asil – daughter of Tuvok and T'Pel – attained Kolinahr, a friend of her father, Kathryn Janeway, was present. ()

Appendices

Apocrypha 
Spock informs Dr. McCoy of his intention to enter Kolinahr at the conclusion of The Lost Years, just after the Enterprise concludes its original five-year mission. Spock predicts that he will never see McCoy, Kirk, or any member of the Enterprise crew again, a prediction that McCoy instinctively refuses to accept.

Forgotten History briefly looks at Spock's reasons for going through Kolinahr, as he feels that his remaining emotions are the reason that he has been mentally compromised by so many creatures during the Enterprises voyages.

The events pictured in Troublesome Minds and Crisis of Consciousness are also given as motivating factors for Spock's decision; at the end of the latter novel, he requests all data from the Vulcan Science Academy on the discipline.

In The Fire and the Rose, Spock again seeks to achieve Kolinahr when faced with a loss of emotional control after Kirk's apparent death on the . He succeeds, but following his mother's death and a confrontation with Leonard McCoy, Spock undergoes a risky procedure to reverse the Kolinahr and restore his ability to feel emotions as he realizes his inability to grieve for his mother.

In the ization of , in the scene where Spock fails to complete his Kolinahr, it is stated to be Kirk's mind he is telepathically connecting with, not V'gers.

External link 
 

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Vulcan
Psychology
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