[ひとつ, hitotsu] (num) (1) one; (n) (2) for one thing (often used in itemized lists); (3) (after a noun) only; (4) (with a verb in negative form) (not) even; (n-adv) (5) just (i.e. "just try it"); (P)#820
[いちじょう, ichijou] (n) (1) one long straight object; streak; beam; ray (of light); wisp (of smoke); (2) one item (in an itemized form); one clause; one passage (in a book); (3) one matter (affair, event, case, incident); (4) the same logic; the same reason; (P)#17226