Dictionary Definition:
Addhan (in cpds. addha˚) [Vedic adhvan, orig. meaning "stretch, length", both of space & time. -- Cases: nom. addhā, gen. dat. addhuno, instr. addhunā, acc. addhānaŋ, loc. addhani; pl. addhā. See also addhāna] 1. (of space) a path, road, also journey (see cpds. & derivations); only in one ster. phrase J iv.384 = v.137 (pathaddhuno paṇṇarase va cando, gen. for loc. ˚addhani, on his course, in his orbit; expld. at iv.384 by ākāsa -- patha -- sankhātassa addhuno majjhe ṭhito and at v.137 by pathaddhagato addha -- pathe gaganamajjhe ṭhito); Pv iii.31 (pathaddhani paṇṇarase va cando; loc. same meaning as prec., expld. at PvA 188 by attano pathabhūte addhani gaganatala -- magge). This phrase (pathaddhan) however is expld. by Kern (Toev. s. v. pathaddu) as "gone half -- way", i. e. on full -- moon -- day. He rejects the expln. of C. -- 2. (of time) a stretch of time, an interval of time, a period, also a lifetime (see cpds.); only in two standard applications viz. (a) as mode of time (past, present & future) in tayo addhā three divisions of time (atita, anāgata, paccuppanna) D iii.216; It 53, 70. (b) in phrase dīghaŋ addhānaŋ (acc.) a very long time A ii.1, 10 (dighaŋ addhānaŋ saŋsāraŋ); Sn 740 (dīghaŋ addhāna saŋsāra); Dh 207 (dīghaŋ addhāna socati); J i.137. gen. dīghassa addhuno PvA 148 (gatattā because a long time has elapsed), instr. dīghena addhunā S i.78; A ii.118; PvA 28.
-- āyu duration of life A ii.66 (dīghaŋ ˚ŋ a long lifetime. -- gata one who has gone the road or traversed the space or span of life, an old man [cp. BSk. adhvagata M Vastu ii.150], always combd. with vayo anuppatto, sometimes in ster. formula with jiṇṇa & mahallaka Vin ii.188; D i.48 (cp. DA i.143); M i.82; Sn pp. 50, 92; PvA 149. -- gū [Vedic adhvaga] a wayfarer, traveller, journeyman Th 255 = S i.212 (but the latter has panthagu, v. l. addhagū); J iii.95 (v. l. patthagu = panthagu); Dh 302.