underfeed I. \| ̷ ̷ ̷ ̷| ̷ ̷\transitive verb Etymology:under (I) + feed 1.: to feed with too little food 2.: to feed with fuel from the underside II. \ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷\adjective : being fed or feeding from beneath < underfeed stroking of a furnace > — opposed to overfeed