1) Become rancid 2) Break down 3) Break down chemically 4) Break up 5) Corrode 6) Crumble 7) Decay 8) Disintegrate 9) Fester 10) French word used in English 11) Go bad 12) Go off 13) Grow mouldy 14) Moulder 15) Perish 16) Putrefy 17) Separate 18) To disintegrate or fragment 19) To rot, decay or putrefy 1) Decay 2) Molder 3) Moulder 4) Rot 
• (v. t.) To separate the constituent parts of; to resolve into original elements; to set free from previously existing forms of chemical combination; to bring to dissolution; to rot or decay. • (v. i.) To become resolved or returned from existing combinations; to undergo dissolution; to decay; to rot.
Broken down by bacteria and fungi.
De`com·pose' transitive verb [ imperfect & past participle Decomposed ; present participle & verbal noun Decomposing .] [ Confer French décomposer . Confer Discompose .] To separate the constituent parts of; to resolve int...
Type: Term Pronunciation: dē′kŏm-pōz′ Definitions: 1. To resolve a compound into its component parts; to disintegrate. 2. To decay; to putrefy.
[v] - break down 2. [v] - separate into constituent elements or parts, as of chemical substances
decompose 1. To separate into constituent parts, or to cause something to separate into its constituent parts. 2. To break down organic matter from a complex to a simpler form, mainly through the action of fungi and bacteria, or to be broken down in this way. 3. To break something down into smaller or simpler parts.
Break a problem down into smaller pieces. 
to break down into parts
molder verb break down; `The bodies decomposed in the heat` verb separate (substances) into constituent elements or parts