1. [n]  the 9th letter of the Roman alphabet
2. [n]  the smallest whole number or a numeral representing this number; "he has the one but will need a two and three to go with it"; "they had lunch at one"
3. [n]  a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks)
4. [adj]  used of a single unit or thing; not two or more; "`ane' is Scottish"

I
This collection of connected short stories is about a writer who is married to a woman with a chronic illness.

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1. \I\ ([imac]).
   1. I, the ninth letter of the English alphabet, takes its
      form from the Ph[oe]nician, through the Latin and the
      Greek. The Ph[oe]nician letter was probably of Egyptian
      origin. Its original value was nearly the same as that of
      the Italian I, or long e as in mete. Etymologically I is
      most closely related to e, y, j, g; as in dint, dent,
      beverage, L. bibere; E. kin, AS. cynn; E. thin, AS.
      [thorn]ynne; E. dominion, donjon, dungeon. In English I
      has two principal vowel sounds: the long sound, as in
      p[=i]ne, [=i]ce; and the short sound, as in p[i^]n. It has
      also three other sounds: (a) That of e in term, as in
      thirst. (b) That of e in mete (in words of foreign
      origin), as in machine, pique, regime. (c) That of
      consonant y (in many words in which it precedes another
      vowel), as in bunion, million, filial, Christian, etc. It
      enters into several digraphs, as in fail, field, seize,
      feign. friend; and with o often forms a proper diphtong,
      as in oil, join, coin. See Guide to Pronunciation,
      [sect][sect] 98-106.
   Note: The dot which we place over the small or lower case i
         dates only from the 14th century. The sounds of I and J
         were originally represented by the same character, and
         even after the introduction of the form J into English
         dictionaries, words containing these letters were, till
         a comparatively recent time, classed together.
   2. In our old authors, I was often used for ay (or aye), yes,
      which is pronounced nearly like it.
   3. As a numeral, I stands for 1, II for 2, etc.
   

2. \I-\, prefix.
   See {Y-}.
   

3. \I\ ([imac]), pron. [poss. {My} (m[imac]) or {Mine}
   (m[imac]n); object. {Me} (m[=e]). pl. nom. {We} (w[=e]);
   poss. {Our} (our) or {Ours} (ourz); object. {Us} ([u^]s).]
   [OE. i, ich, ic, AS. ic; akin to OS. & D. ik, OHG. ih, G.
   ich, Icel. ek, Dan. jeg, Sw. jag, Goth. ik, OSlav. az', Russ.
   ia, W. i, L. ego, Gr. 'egw`, 'egw`n, Skr. aham. [root]179.
   Cf. {Egoism}.]
   The nominative case of the pronoun of the first person; the
   word with which a speaker or writer denotes himself.