Deduct vs Substrate - What's the difference?

As a verb deduct

is to take one thing from another; remove from; make smaller by some amount.

(en verb)

To take one thing from another; remove from; make smaller by some amount.

I will deduct the cost of the can of peas from the money I owe you.

(en noun)

(biochemistry) What an enzyme acts upon.

(biology) A surface on which an organism grows or to which it is attached.

The rock surface of a rockpool is the substrate for a sessile organism such as a limpet.

An underlying layer; a substratum.

(linguistics) A language that is replaced in a population by another language and that influences the language imposed on its speakers.

(plating) A metal which is plated with another metal which has different physical properties.

(construction) A surface to which a substance adheres.

The substance lining the bottom edge of an enclosure.

The substrate of an aquarium can affect the water's acidity.

Stream substrate affects fish longevity.

(substrat)

(obsolete) To strew or lay under.

* Boyle

The melted glass being supported by the substrated sand.

(en adjective)

Having very slight furrows.