Conservative is...

Standard political usage tells us that Republicans are conservative and Democrats are liberal. This is not absolutely true, but relatively so.
Conservative legal thought holds that precedent should be upheld. Whether the precedent is Roe vs Wade or Dred Scott doesn't particularly matter in the legal/judiciary use of 'conservative'. A legal/judiciary conservative would be opposed to legalization of abortion because the precedent is in place, regardless of the moral, philosophical or religious feeling they might have about the procedure. Their conservatism would mean they are philosophically committed to earlier decisions and find change to be more distasteful and the status quo. This is illustrated by the sneering talking point of 'activist judges'.
Conservative economic thought holds that classsical economics are the true word. Market forces are good. Regulation, taxation, protectionism, subsidy and all forms of government market involvement are bad. Always. Again, the purity of the old ideas appeals to the conservative mind. The conservative mindset is closed to new thoughts and truths that suggest classical established thoughts could be anything other than righteous and touched by the hand of their economic God. Modifications to the godly market force is heresy.
Conservative religious thought holds that the theological and philosophical ideas of the elders (whoever the hell they might be) are handed down almost directly from the Almighty. These ideas must not be questioned or altered. Again, adherence to a rigid dogma is the key to conservatism.
In all examples, conservative thought is rigid and closed. It stubbornly adheres to established ideas in the face of any challenge. Closed-mindedness is valued in conservative minds as if it were righteousness. It is not.