Bhāvanā: 'mental development' lit. 'calling into existence, producing' is what in English is generally but rather vaguely called 'meditation'. One has to distinguish 2 kinds: development of tranquillity samatha-bhāvanā, i.e. concentration samadhi, and development of insight vipassana-bhāvanā, i.e. understanding panna.
These two important terms, tranquillity and insight see: samatha-vipassanā, are very often met with and explained in the Sutta, as well as in the Abhidhamma.
Tranquillity samatha is the concentrated, unshaken, peaceful, and therefore undefiled state of mind, whilst insight vipassanā is the intuitive insight into the impermanence, misery and impersonality anicca dukkha anattā see: tilakkhana of all bodily and mental phenomena of existence, included in the 5 groups of existence, namely, materiality, feeling, perception, mental constructions and consciousness; see: khandha.
Tranquillity, or concentration of mind, according to Sankhepavannana Commentary to Abhidhammattha-sangaha, bestows a threefold blessing: favourable rebirth, present happy life, and purity of mind which is the condition of insight. Concentration samādhi is the indispensable foundation and precondition of insight by purifying the mind from the 5 mental defilements or hindrances nīvarana, whilst insight vipassanā produces the 4 supra mundane stages of Nobility and deliverance of mind. The Buddha therefore says: May you develop mental concentration, o Bhikkhus; for who is mentally concentrated, sees things according to reality see: XXII, 5. And in Mil. it is said: Just as when a lighted lamp is brought into a dark chamber, the lamp-light Will destroy the darkness and produce and spread the light, just so will insight, once arisen, destroy the darkness of ignorance and produce the light of knowledge.
Vis.M III-XI gives full directions how to attain full concentration and the absorptions jhāna by means of the following 40 meditation subjects kammatthāna:
10 kasina-exercises see: kasina. These produce the 4 absorptions
10 loathsome subjects asubha. These produce the 1st absorption.
10 recollections anussati: of the Buddha buddhānussati, the Doctrine dhammānussati, the Brotherhood of the Noble Ones sanghānussati, morality, generosity, the divine beings, death maranasati, the body kāyagatāsati,, in-and-outbreathing ānāpāna-sati and peace upasamānussati, . Among these, the recollection or awareness or mindfulness of in-and-out breathing may produce all the 4 absorptions, that of the body the 1st absorption, the rest only neighbourhood-concentration upacāra-samādhi, see: samadhi.
4 sublime abodes brahma-vihāra: loving-kindness, Pity, altruistic joy, equanimity mettā, karunā, muditā, upekkhā. Of these, the first 3 exercises may produce 3 absorptions, the last one the 4th absorption only.
4 immaterial spheres arūpāyatana see. jhāna : of unbounded space, unbounded consciousness, nothingness, neither-perception-nor-non-perception. These are based upon the 4th absorption.
1 perception of the loathsomeness of food āhāre patikkūla-saññā, which may produce neighbourhood-concentration
1 analysis of the 4 elements catudhātu-vavatthāna see. dhātu-vavatthāna, which may produce neighbourhood-concentration.
Mental development forms one of the 3 kinds of meritorious action puñña-kiriya-vatthu. 'Delight in meditation' bhāvanā-rāmatā is one of the noble usages ariya-vamsa.
Maha Thera Nyanatiloka. Manual of Buddhist Terms and Doctrines, Buddhist Publication Society, first edition 1952.