- To organize into a labor union.
- To cause to join a labor union.
- To organize or join a labor union.
- To give the character of a union, and specifically of a trade-union, to; transform into, organize as, or incorporate in a (trade-) union; cause to join a (trade-) union.
- To <xref>organize</xref> <xref>workers</xref> into a <xref>union</xref>.
- form or join a union
- recruit for a union or organize into a union