A definition item contains zero to multiple DefinitionTerm and definitions (any Block)
public class DefinitionItem : ContainerBlock, IBlock, IMarkdownObject, IList<Block>, ICollection<Block>, IReadOnlyList<Block>, IReadOnlyCollection<Block>, IEnumerable<Block>, IEnumerable
kind:method, kind:property, kind:ctor. Press Esc to clear.DefinitionItem(BlockParser)Initializes a new instance of the DefinitionItem class.OpeningCharacterGets or sets the opening character for this definition item (either `:` or `~`)