main·tain / mānˈtān/ • v. [tr.] 1. cause or enable (a condition or state of affairs) to continue: the need to maintain close links between industry and schools. ∎  keep (something) at the same level or rate: agricultural prices will have to be maintained. ∎  keep (a building, machine, or road) in good condition or in working order by checking or repairing it regularly. ∎  hold (a position) in the face of attack or competition: the objective to maintain a competitive market position.2. provide with necessities for life or existence: the allowance covers the basic costs of maintaining a child. ∎  keep (a military unit) supplied with equipment and other requirements. ∎ archaic give one's support to; uphold: the king swears he will maintain the laws of God.3. state something strongly to be the case; assert: [tr.] he has always maintained his innocence | he had persistently maintained that he would not stand against his old friend | [with direct speech] “It was not an ideology at all,” she maintained. DERIVATIVES: main·tain·a·bil·i·ty / ˌmānˌtānəˈbilətē/ n.main·tain·a·ble adj.

maintain support the person or cause of XIII; † practise habitually; carry on, continue; support, provide for XIV. ME. mainte(i)ne, repr. tonic stem of (O)F. maintenir (AN. maintener):- Rom. *manūtenēre, f. L. manū, abl. of manus hand + tenēre hold.
So maintenance † demeanour; support of a party or cause; provision of livelihood. XIV. — OF.