see references

major flank and minor flank

http://www.websters-online-dictionary.org/definitions/Flank

minor flank moves:
http://is.gd/9CmrJP

And so Porfirio Zamora served as a cavalry commander for Júarez, while Díaz, who was then barely emerging as an important historical figure, led another major flank of troops at the Battle of Puebla.
http://www.tpwmagazine.com/archive/2002/may/ed_3/

Sounds like a word derived from French and used in Flemish, but, I could be wrong on that bit.

We know a flank is a side, that could be anything, maybe the side of a dog, a flank in a group like an army, or the flanker in a rugby math, but the bit ''ement'' adds a different sense to the word that says more than only flank, or the flanker or flanking alone.

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On the left flank, the 8th Canadian Infantry Brigade captured Wolf Copse and secured its objective line but was ultimately forced to drop a defensive flank 300 yards (270 m) back to link up with the 63rd (Royal Naval) Division, the flanking division of the British Fifth Army.





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Note added at 14 hrs (2012-07-11 22:34:44 GMT)
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That was rugby match and the spelling checker failed, bad, bad spelling checker; lose 5 points and go to start!