I have my book with the W's right here - PM away!
A direct ancestor is Patriot to child to child to child to child to you (with more or less generations).
A collatertal ancestor would be Patriot to niece/nephew to child to niece/nephew to child to child to you (with various mixes). The DAR doesn't accept collateral descendants, but if you've found that an Uncle John served, go back a generation, see if his father/mother gave service (remember, "gave patriotic service"), then come down on a direct lineage. One lineage society that
does accept collateral ancestors is the UDC; I'm not sure of others.