gagana : [nt.] the sky.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]

Gagana (nt.) the sky (with reference to sidereal motions); usually of the moon: g˚ majjhe puṇṇacando viya J i.149, 212; g˚ tale canda -- maṇḍalaŋ J iii.365; cando g˚ majjhe ṭhito J v.137; cando gagane viya sobhati Vism 58; g˚ tale candaŋ viya DhA i.372; g˚ tale puṇṇacanda "the full -- moon in the expanse of the heavens" VvA 3; g˚ talamagga the (moon's) course in the sky PvA 188; etc. Of the sun: suriyo ākāse antalikkhe gaganapathe gacchati Nd2 on Sn 1097. Unspecified: J i.57; Vism 176 (˚tal -- âbhimukhaŋ).

Pali-English Dictionary, TW Rhys Davids, William Stede,

gagana n. the atmosphere, sky, firmament R. Suśr. Ragh. NārUp. &c
• talc Bhpr.
 

Sanskrit-English Dictionary, by M. Monier William

nam mkha'

[translation-san] {LCh,C,MSA} ākāśa

[translation-san] {C} abhyavakāśa

[translation-san] {C} kha

[translation-san] {C} gagana

[translation-eng] {Hopkins} space; sky

[translation-eng] {C} open space; open place; empty space; firmament

Jeffrey Hopkins' Tibetan-Sanskrit-English Dictionary

nam mkhar

[translation-san] {C} gagana

[translation-eng] {Hopkins} in the sky; in space

[translation-eng] {C} sky; firmament

Jeffrey Hopkins' Tibetan-Sanskrit-English Dictionary