1) Religious doctrine 2) Theological doctrine 
• (a.) Of the same kind or nature; having the same substance or essence; coessential.
Con`sub·stan'tial adjective [ Latin consubstantialis ; con- + substantialis : confer French consubstantiel . See Substantial .] Of the same kind or nature; having the same substance or essence; coessential. « Christ Jesus . . . coeternal and consubstantial...
Consubstantial is an equivalent for the Greek term homoousios, the true signification of which disturbed the Christian church early in the 4th century, as it was supposed to affect the orthodoxy of Christians regarding the Trinity, according as it might be understood rightly or the contrary. The Athanasians, or Trinitarians, at the council of Nice ...
[adj] - (Christian theology) regarded as the same in substance or essence (as of the three persons of the Trinity)
adjective regarded as the same in substance or essence (as of the three persons of the Trinity)
of one and the same substance, essence, or nature.