Hello Pali friends,
First the essential part of article from Margaret Cone's dictionary:
ārammaṇa, n. (and mfn.) [cf S. ārambhaṇa, BHS ārambaṇa; cf also S., BHS ālambana] (pl. nom. ~āni, ~ā; acc. ~āni and perhaps ~e),
1. (n.) basis, starting-point (for producing or initiating activity), footing; basis of meditation; object, object of concentration, sense-object; ...
2. (mfn.) being a basis or object; ? ...
And now some suttas where one can see both 'footing' and 'starting-point' meanings:
"One attached is unreleased; one unattached is released. Should consciousness, when standing, stand attached to (a physical) form, supported by form (as its object), landing on form, watered with delight, it would exhibit growth, increase, & proliferation.
Upayo bhikkhave, avimutto, anupayo vimutto, rūpūpayaṃ vā bhikkhave, viññāṇaṃ tiṭṭhamānaṃ tiṭṭheyya, rūpārammaṇaṃ rūpappatiṭṭhaṃ nandūpasecanaṃ vuddhiṃ virūḷahiṃ vepullaṃ āpajjeyya,
(similarly with other aggregates)
"Were someone to say, 'I will describe a coming, a going, a passing away, an arising, a growth, an increase, or a proliferation of consciousness apart from form, from feeling, from perception, from fabrications,' that would be impossible.
Yo bhikkhave evaṃ vadeyya: ahamaññatra rūpā aññatra vedanāya aññatra saññāya aññatra saṃkhārehi viññāṇassa āgatiṃ vā gatiṃ vā cutiṃ vā uppattiṃ vā vuddhiṃ vā virūḷhiṃ vā vepullaṃ vā paññāpessāmīti netaṃ ṭhānaṃ vijjati.
"If a monk abandons passion for the property of form, ... feeling, ... perception, ... fabrications, ...
consciousness, then owing to the abandonment of passion, the support is cut off, and there is no landing of consciousness. Consciousness, thus not having landed, not increasing, not concocting, is released. Owing to its release, it is steady. Owing to its steadiness, it is contented. Owing to its contentment, it is not agitated. Not agitated, he (the monk) is totally unbound right within. He discerns that 'Birth is ended, the holy life fulfilled, the task done. There is nothing further for this world.'"
Rūpadhātuyā ce bhikkhave, bhikkhuno rāgo pahīno hoti, rāgassa pahānā vocchijjatārammaṇaṃ, patiṭṭhā viññāṇassa na hoti, vedanādhātuyā ce bhikkhave bhikkhuno rāgo pahīno hoti, rāgassa pahānā vocchijjatārammaṇaṃ, patiṭṭhā viññāṇassa na hoti, saññādhātuyā ce bhikkhave bhikkhuno rāgo pahīno hoti, rāgassa pahānā vocchijjatārammaṇaṃ, patiṭṭhā viññāṇassa na hoti, saṃkhāradhātuyā ce bhikkhave bhikkhuno rāgassa pahino hoti. Rāgassa pahānā vocchijjatārammaṇaṃ patiṭṭhā viññāṇassa na hoti. Viññāṇadhātuyā ce bhikkhave, bhikkhunā rāgo pahīno hoti. Rāgassa pahānā vocchijjatārammaṇaṃ, patiṭṭhā viññāṇassa na hoti, tadappatiṭṭaṭhitaṃ viññāṇaṃ avirūḷhaṃ anabhi saṅkhacca vimuttaṃ, vimuttattā ṭhitaṃ ṭhitattā santusitaṃ, santusitattā na paritassati aparitassaṃ paccattaṃ yeva parinibbāyati. 'Khīṇā jāti, vusitaṃ brahmacariyaṃ, kataṃ karaṇīyaṃ, nāparaṃ itthattāyā'ti pajānātīti.
http://www.accesstoinsight.org/tipitaka ... .than.html
So, when used in conjunction with 'viññāṇā', 'ārammaṇa' means some element of 'nama-rupa' (which contains four other aggregates), on which consciousness lands and proliferates.
Dhammasangani lists types of 'ārammaṇa' according to sense door:
1. Katame dhammā kusalā? Yasmiṃ samaye kāmāvacaraṃ kusalaṃ cittaṃ uppannaṃ hoti somanassasahagataṃ ñāṇasampayuttaṃ rūpārammaṇaṃ vā saddārammaṇaṃ vā gandhārammaṇaṃ vā rasārammaṇaṃ vā phoṭṭhabbārammaṇaṃ vā dhammārammaṇaṃ vā yaṃ yaṃ vā panārabbha, tasmiṃ samaye phasso hoti, vedanā hoti, saññā hoti, cetanā hoti, cittaṃ hoti, vitakko hoti, vicāro hoti, pīti hoti, sukhaṃ hoti, cittassekaggatā hoti, ...
And 'dhammā' as an objects of intellect (mano) are explained as 'dhamma-arammana':
Dhammāti nibbānaṃ muñcitvā avasesā dhammārammaṇadhammā.