TCOM may refer to:
- TCOM (linguistics), time of completion – a temporal reference for establishing tense
- Texas College of Osteopathic Medicine, a college of the University of North Texas in Fort Worth, Texas
- The Colour of Magic, a Discworld novel by Terry Pratchett
- Transcutaneous oxygen measurement - an assessment of the oxygen level beneath the skin
In linguistics, T (always written as uppercase T plus uppercase COM in subscript) is an abbreviation for the time of completion, a secondary temporal reference in establishing tense.
Grammatical tense represents the contrast between two measurements along the timeline of an utterance, with one of those measurements being the time of utterance T (the time at which the actual utterance is made). T is always the primary point of reference for tense. There are three additional references to which T can be contrasted: T — the time of assertion, T — the time of completion, and T — the time of evaluation; these are secondary references. The type used for the secondary reference is determined by aspect and type of utterance.
T is the point in time at which a verb is completed. T is used with perfected forms. In perfected non-durational aspects it represents the time by which a verb is finished, as in English “I have eaten dinner.” In perfected durational aspects it represents either the time at which a verb is finished, or more normally, a time up to which the verb is completed (but that it may continue beyond); this meaning of interrupting the verb is the more standard use of this form and allows the duration of the verb to be measured up to a given point (T). Consider “I had been eating for 2 hours by 7pm,” in which an action (eating) has a duration, of which two hours of it is completed as of 7pm.