Bob's your uncle

Meaning

Used to describe the means of straightforwardly obtaining a successful result; for example, 'left over right; right over left, and bob's your uncle - a reef knot'.

Origin

This is one of those phrases that keep etymologists in business in that no one is sure of its origin. As with all such mysteries, there are plenty of suggestions but we will content ourselves here with the most plausible three:

The expression is often said to derive from the supposed nepotism of the British Prime Minister Lord (Robert) Salisbury, who appointed a favourite nephew, Arthur Balfour, to several political posts in the 1880s. Balfour had considerable talents and went on to become Prime Minister himself, but his early political appointments were considered inappropriate as he showed no interest in public work and at the time preoccupied himself with philosophy and an active social life. It is unlikely that Arthur Balfour would ever have become a celebrated politician without the patronage of his influential uncle. Piers Brendon, in Eminent Edwardians, 1979, writes:

"... in 1887, Balfour was unexpectedly promoted to the vital front line post of Chief Secretary for Ireland by his uncle Robert, Lord Salisbury."

The link here between an uncle Bob who was Prime Minister and a passport to an easy life is easy to make. In fact, that very neatness has the odour of a folk-etymology.

A second interpretation has that it the phrase derives from the slang term 'all is bob', meaning 'all is well'. That term is listed in Captain Francis Grose’s Dictionary of the Vulgar Tongue, 1785:

A shoplifter’s assistant, or one that receives and carries off stolen goods. All is bob; all is safe.

The slang word 'bob', with the 'shoplifter's assistant' meaning, had been in circulation for some years at that time and is defined as such in Nathan Bailey's Dictionary of Canting and Thieving Slang, 1721.

The third potential source is in a music hall song written by John P. Long, and published in 1931 - Follow your Uncle Bob. The lyrics include:

Bob's your uncle
Follow your Uncle Bob
He knows what to do
He'll look after you

The song was sung and recorded by Florrie Forde, the celebrated music hall artiste of the early 20th century.

Eric Partridge lists it in his A Dictionary of Slang and Unconventional English, 1937. He states it as dating from circa 1890, although he presents no evidence for that.

The difficulty with the first two suggested origins is the date. The phrase itself isn't known until the 1930s. It would seem odd for a phrase to be coined about the nepotism of an uncle and nephew long after both prime ministers were out of office and politically irrelevant. The 'all is bob' origin is from a century or so earlier and appears to have little reason the be connected to 'bob's your uncle' other than that they both contain the word bob.

Step forward, Florrie Forde.