These words are all applied to persons who have passed youth and middle age. Old is the most general word, with the widest range of application. It may indicate strictly chronological age, referring to the latter part of life: old age; an old woman. But it may also focus on the negative qualities associated with old age, as loss of health, strength or motivating force: She was old at 40, but he still has his youthful spirit at 75. Aged often indicates a longer life-span than old , applying to persons of very advanced years; it is more formal than old as well as more limited in application. Specifically, it often points to changes wrought by ageing, suggesting a definite physical decline, though not necessarily implying disability: an aged man advancing slowly, with the aid of a cane; an aged crone. In a social context, the designation "home for the aged " has largely replaced the plain (or blunt) term "old people’s home"; the former may be preferred because it more easily suggests debilitation that might demand institutional care. Elderly is more favourable than either of the foregoing. It is a polite term, often connoting the dignity rather than the weight of years: their elderly parents. An elderly person has passed middle age but is generally regarded as younger than an old person, both in age and in vigour: a resort hotel catering for elderly couples; an elderly gentleman, silver-haired, with a twinkle in his eye.

Superannuated and senile stress the negative aspects of ageing. Superannuated emphasizes the idea of being considered too old to continue in one’s job. In a specific sense, a superannuated person is one who has been retired because he has passed an arbitrary age limit, such as 65: a superannuated schoolteacher. In an extended sense, the word means too old to be useful or efficient and has a disparaging tone: a superannuated mechanic, frail of body and hard of hearing, but still given light work by kindly people in the neighbourhood. Senile implies a much more marked incapacity or decline. A person may be aged or superannuated without being senile . Senile comes from the Latin word for old and points to mental or physical infirmity accompanying extreme old age. Senile atrophy, for example, involves a wasting away of tissue and a consequent emaciation of the body. Most specifically, however, in general use, senile stresses the enfeebling effects of age on the mind.

• She has grown senile – her memory is going and she is in her dotage, or her second childhood; He is as old as she is, but his mind is as keen and clear as ever.

Venerable and patriarchal stress the positive aspects of ageing. Venerable emphasizes the reverence, respect and deference owed to one’s elders. It focuses on the dignity of advanced age, implying that the person held in reverence is worthy of veneration because of wisdom, position or achievement: a venerable father; a venerable sage. Venerable can also suggest a distinguished appearance: venerable white hairs. Patriarchal means like a patriarch – the leader of a family or father of a race. It is a close synonym of venerable but carries added overtones of power and authority, such as might be exercised by an ecclesiastical patriarch or bishop.

• The head of the firm was a patriarchal old man who struck awe into his employees; an actor with a hoary beard and patriarchal bearing, often cast in Biblical epics; a patriarchal tribal chief.