1flank 
/ˈflæŋk/ noun
plural flanks /ˈflæŋk/ noun [count] 1 : the area on the side of an animal (such as a horse) between the ribs and the hip
▪ She gently patted the horse's flank. — see picture at horse 2 : the right or left side of a military formation
▪ They attacked the enemy on both flanks. 3 : the side of something
▪ the eastern flank of a volcano
▪ She gently patted the horse's flank. — see picture at horse
▪ They attacked the enemy on both flanks.
▪ the eastern flank of a volcano
