old man. veteran, patriarch, Nestor, elder, oldster, Methuselah, dotard; gaffer, crone, geezer; centenarian, octogenarian, sexagenarian, nonagenarian.
old-time, a. [late], [former], [quondam].
old woman. beldame, crone, gammer; [witch], [hag], harridan.
old-womanish, a. anile.
old-womanishness, n. anility.
omen, n. [foretoken], [sign], [augury], portent, [presage], prognostic, auspice.
ominous, a. [portentous], monitory, premonitory, [threatening].
omission, n. default, [oversight], [neglect], pretermission, [omittance], non-performance.
omit, v. leave [out], [slap], pretermit, [disregard], [neglect], [overlook], [ignore], delete.
omittance, n. [omission], [forbearance], default, [neglect], [oversight].