Definitions of attachment:

noun: the act of attaching or affixing something
noun: faithful support for a religion or cause or political party
noun: a supplementary part or accessory
noun: a connection that fastens things together
noun: a writ authorizing the seizure of property that may be needed for the payment of a judgment in a judicial proceeding
noun: a feeling of affection for a person or an institution
noun: the act of fastening things together