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VAIN / VEIN / VANE
(1) A vein is a blood vessel or a distinctive style.
(2) Vain means 'self admiring' or 'futile'. The term 'in vain' means 'without
success'.
(3) A vane is a stabilizing fin or blade.
The words 'vein', 'vain' and 'vane' sound identical, but their meanings are very
different.
A blood vessel that carries blood from the capillaries towards the
heart.
veins
varicose veins
A distinctive style or
manner.
Mr
Mellor continued in the same vein despite several reprimands.
A layer of ore or
mineral between
layers of rock.
mineral vein
running
through
rock
The ribs that support an insect's wing.
veins in an insect's wing
Vain
The adjective
'vain' means 'conceited' or 'self admiring'. 'Vain' can also mean
'fruitless'. In this meaning, it is often seen as 'in vain' meaning
'without success' or 'in a futile manner'.
Examples:
Petra is so
vain. She spends half her time looking in the mirror.
I tried in
vain to pull the boat ashore, but it was just too heavy.
Vane
The noun 'vane'
denotes a blade or a fin usually used to stabilize an object in the air or in
water. It is most commonly seen in the word weathervane.
Examples:
The
stabilizing vane has come loose.
The steel
casing protects the vane from damage in the event that the
vessel hits the
rocks.
Easily Confused Words
Mr
Mellor continued in the same vein despite several reprimands. 
