1520s, "indicate, express, set forth, convey to the mind as the meaning or thing intended," from the noun in English and from Anglo-French purporter (c. 1300), from Old French purporter "to contain, convey, carry; intend," from pur- (from Latin pro- "forth;" see pur-) + Old French porter "to carry," from Latin portare "to carry" (from PIE root *per- (2) "to lead, pass over"). Related: Purported; purporting.
"native carbonate of sodium," 1680s, from French natron (1660s), which is said to be directly from Arabic natrun, itself from Greek nitron, itself possibly of Eastern origin (see nitre). Medieval Latin and Paracelsus (16c.) had a form anatron, from Arabic with the article assimilated (an-natron). It is the source of the chemical symbol Na for sodium and the word-forming element natro-, used in the names of minerals to indicate the presence of sodium.
c. 1200, noten, "observe, take mental note of, mark carefully," from Old French noter "indicate, designate; take note of, write down," from Latin notare "to mark, note, make a note," from nota "mark, sign, note, character, letter" (see note (n.)). Sense of "mention separately or specially among others" is from late 14c. Meaning "to set down in writing, make a memorandum of" is from early 14c. Related: Noted; noting.
1690s, "serving to distinguish," especially of a mark or sign added to a letter to distinguish it from another of similar form or indicate a peculiar accent, tone, or stress, from Latinized form of Greek diakritikos "that separates or distinguishes," from diakrinein "to separate one from another," from dia "between" (see dia-) + krinein "to separate, decide, judge" (from PIE root *krei- "to sieve," thus "discriminate, distinguish"). As a noun, "a diacritical mark," from 1866. Related: Diacritical.