OK, so this is a going to be a terminological peeve. The above images show: (left) a sparrow, which is a chunky, short-tailed and typically brown garden bird; and (right) a swallow, a streamlined migratory bird, brightly coloured in many species, with a long forked tail. How could anyone confuse them?
And yet, I've noticed lately a highly prevalent misnomer of referring to the trad swallow tattoo design - most commonly based on the red-and-blue North American barn swallow - as a "sparrow tattoo".
Very occasionally it really is a sparrow. But (judging by a sample) in the vast majority of the 110,000 Google images hits for "sparrow tattoo", the bird depicted is clearly a swallow - the colourful bird with a forked tail - exactly the same as in the 146,000 Google images hits that correctly describe it as a "swallow tattoo".
I can't at this instant fathom the genesis of this. Did it arise merely from the phonetic similarity; or was it helped along by association with Jack Sparrow in Pirates of the Caribbean, who as a mariner has a swallow tattoo (above)?
Addendum: And I quite forgot another piece of terminology in the same territory. A Monroe piercing is a piercing above the left upper lip, named after the location of Marilyn Monroe's