table (noun), tabular (adjective): table is a French word, from Latin tabula “a board, plank, writing tablet,” of unknown prior origin. In addition to representing a tablet or writing table, even in Roman times the word came to stand for the document or contract being written on the tablet. In English, as early as the 14th century the word also came to refer to the arrangement of words and numbers that were occasionally included in a document. American students are most commonly taught to graph a function by making a table of values. In symbolic logic, students often make a truth table to find the truth value of a compound statement. The tabular digits of a number are all the digits in sequence from the first nonzero digit to the last nonzero digit. For example, the tabular digits of 0.03204 and 320400 are the same, namely 3204. The term tabular takes its name from the fact that the base-ten logarithms of 0.03204 and 320400 would both be looked up under 3204 in a table of logarithms. Now that tables of logarithms are all but extinct, the word tabular is rarely used in the above sense. Still in use is the tabular key on a computer keyboard, now almost always called the tab key, which moves you from column to column in a table.

tac-locus, plural tac-loci (noun): the first component is from Latin tactus, past participle of tangere “to touch.” The Indo-European root is tag- “to touch.”