Heraldic line of division used in ordinaries or in partitions of fields. It resembles castle crenelations.
<a href="//commons.wikimedia.org/wiki/User:GreiiEquites" title="User:GreiiEquites">GreiiEquites</a>
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<cite class="book" style="font-style:normal">Bandeira, Luís Stubbs Saldanha Monteiro (1984)    (in portuguese)  <i> Vocabulário Heráldico</i> (4th ed.), <a href="https://en.wikipedia.org/wiki/en:Lisbon" class="extiw" title="w:en:Lisbon"><span title="capital city of Portugal">Lisbon</span></a>:  Mama Sume  <small></small></cite>