Source: Noto Sans

U+00AA Feminine Ordinal Indicator

U+00AA was added in Unicode version 1.1 in 1993. It belongs to the block U+0080 to U+00FF Latin-1 Supplement in the U+0000 to U+FFFF Basic Multilingual Plane.

This character is a Other Letter and is mainly used in the Latin script.

The glyph is a superscript version of the glyph Latin Small Letter A. Its width in East Asian texts is determined by its context. It can be displayed wide or narrow. In bidirectional text it is written from left to right. When changing direction it is not mirrored. If its East Asian Width is “narrow”, U+00AA forms a word with similar characters, which prevents a line break inside it. Otherwise it allows line breaks around it, except in some numeric contexts.

The Wikipedia has the following information about this codepoint:

In written languages, an ordinal indicator is a character, or group of characters, following a numeral denoting that it is an ordinal number, rather than a cardinal number. In English orthography, this corresponds to the suffixes -st, -nd, -rd, -th in written ordinals (represented either on the line 1st, 2nd, 3rd, 4th or as superscript, 1^st, 2^nd, 3^rd, 4^th).
Also commonly encountered are the superscript or superior (and often underlined) masculine ordinal indicator, º, and feminine ordinal indicator, ª, originally from Romance and then via the cultural influence of Italian, as in 1º primo and 1ª prima. In correct typography, the ordinal indicators ª and º should be distinguishable from other characters.
The practice of underlined (or doubly underlined) superscripted abbreviations was common in 19th-century writing (not limited to ordinal indicators in particular, and also extant in the numero sign №), and was also found in handwritten English until at least the late 19th century (e.g. first abbreviated 1^st or 1^st).

Representations

System	Representation
Nº	170
UTF-8	C2 AA
UTF-16	00 AA
UTF-32	00 00 00 AA
URL-Quoted	%C2%AA
HTML hex reference	ª
Wrong windows-1252 Mojibake	Âª
HTML named entity	&ordf
HTML named entity	ª
Encoding: EUC-KR (hex bytes)	A8 A3
Encoding: ISO-8859-15 (hex bytes)	AA
Encoding: MACINTOSH (hex bytes)	BB
Encoding: WINDOWS-1252 (hex bytes)	AA
Encoding: WINDOWS-1254 (hex bytes)	AA
Encoding: WINDOWS-1258 (hex bytes)	AA
L^AT_EX	\textordfeminine
AGL: Latin-1	ordfeminine
AGL: Latin-2	ordfeminine
AGL: Latin-3	ordfeminine
AGL: Latin-4	ordfeminine
AGL: Latin-5	ordfeminine
Adobe Glyph List	ordfeminine
digraph	-a

Elsewhere

Complete Record

Property	Value
Age (age)	1.1 (1993)
Unicode Name (na)	FEMININE ORDINAL INDICATOR
Unicode 1 Name (na1)	—
Block (blk)	Latin-1 Supplement
General Category (gc)	Other Letter
Script (sc)	Latin
Bidirectional Category (bc)	Left To Right
Combining Class (ccc)	Not Reordered
Decomposition Type (dt)	superscript
Decomposition Mapping (dm)	Latin Small Letter A
Lowercase (Lower)	✔
Simple Lowercase Mapping (slc)	Feminine Ordinal Indicator
Lowercase Mapping (lc)	Feminine Ordinal Indicator
Uppercase (Upper)	✘
Simple Uppercase Mapping (suc)	Feminine Ordinal Indicator
Uppercase Mapping (uc)	Feminine Ordinal Indicator
Simple Titlecase Mapping (stc)	Feminine Ordinal Indicator
Titlecase Mapping (tc)	Feminine Ordinal Indicator
Case Folding (cf)	Feminine Ordinal Indicator
ASCII Hex Digit (AHex)	✘
Alphabetic (Alpha)	✔
Bidi Control (Bidi_C)	✘
Bidi Mirrored (Bidi_M)	✘
Composition Exclusion (CE)	✘
Case Ignorable (CI)	✘
Changes When Casefolded (CWCF)	✘
Changes When Casemapped (CWCM)	✘
Changes When NFKC Casefolded (CWKCF)	✔
Changes When Lowercased (CWL)	✘
Changes When Titlecased (CWT)	✘
Changes When Uppercased (CWU)	✘
Cased (Cased)	✔
Full Composition Exclusion (Comp_Ex)	✘
Default Ignorable Code Point (DI)	✘
Dash (Dash)	✘
Deprecated (Dep)	✘
Diacritic (Dia)	✘
Emoji Modifier Base (EBase)	✘
Emoji Component (EComp)	✘
Emoji Modifier (EMod)	✘
Emoji Presentation (EPres)	✘
Emoji (Emoji)	✘
Extender (Ext)	✘
Extended Pictographic (ExtPict)	✘
FC NFKC Closure (FC_NFKC)	Feminine Ordinal Indicator
Grapheme Cluster Break (GCB)	Any
Grapheme Base (Gr_Base)	✔
Grapheme Extend (Gr_Ext)	✘
Grapheme Link (Gr_Link)	✘
Hex Digit (Hex)	✘
Hyphen (Hyphen)	✘
ID Continue (IDC)	✔
ID Start (IDS)	✔
IDS Binary Operator (IDSB)	✘
IDS Trinary Operator and (IDST)	✘
IDSU (IDSU)	0
ID_Compat_Math_Continue (ID_Compat_Math_Continue)	0
ID_Compat_Math_Start (ID_Compat_Math_Start)	0
Ideographic (Ideo)	✘
InCB (InCB)	None
Indic Mantra Category (InMC)	—
Indic Positional Category (InPC)	NA
Indic Syllabic Category (InSC)	Other
Jamo Short Name (JSN)	—
Join Control (Join_C)	✘
Logical Order Exception (LOE)	✘
Math (Math)	✘
Noncharacter Code Point (NChar)	✘
NFC Quick Check (NFC_QC)	Yes
NFD Quick Check (NFD_QC)	Yes
NFKC Casefold (NFKC_CF)	Latin Small Letter A
NFKC Quick Check (NFKC_QC)	No
NFKC_SCF (NFKC_SCF)	Latin Small Letter A
NFKD Quick Check (NFKD_QC)	No
Other Alphabetic (OAlpha)	✘
Other Default Ignorable Code Point (ODI)	✘
Other Grapheme Extend (OGr_Ext)	✘
Other ID Continue (OIDC)	✘
Other ID Start (OIDS)	✘
Other Lowercase (OLower)	✔
Other Math (OMath)	✘
Other Uppercase (OUpper)	✘
Prepended Concatenation Mark (PCM)	✘
Pattern Syntax (Pat_Syn)	✘
Pattern White Space (Pat_WS)	✘
Quotation Mark (QMark)	✘
Regional Indicator (RI)	✘
Radical (Radical)	✘
Sentence Break (SB)	Lower
Soft Dotted (SD)	✘
Sentence Terminal (STerm)	✘
Terminal Punctuation (Term)	✘
Unified Ideograph (UIdeo)	✘
Variation Selector (VS)	✘
Word Break (WB)	Alphabetic Letter
White Space (WSpace)	✘
XID Continue (XIDC)	✔
XID Start (XIDS)	✔
Expands On NFC (XO_NFC)	✘
Expands On NFD (XO_NFD)	✘
Expands On NFKC (XO_NFKC)	✘
Expands On NFKD (XO_NFKD)	✘
Bidi Paired Bracket (bpb)	Feminine Ordinal Indicator
Bidi Paired Bracket Type (bpt)	None
East Asian Width (ea)	ambiguous
Hangul Syllable Type (hst)	Not Applicable
ISO 10646 Comment (isc)	—
Joining Group (jg)	No_Joining_Group
Joining Type (jt)	Non Joining
Line Break (lb)	Ambiguous (Alphabetic or Ideographic)
Numeric Type (nt)	none
Numeric Value (nv)	not a number
Simple Case Folding (scf)	Feminine Ordinal Indicator
Script Extension (scx)
Vertical Orientation (vo)	R