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Abbreviations and Acronyms Found in Genealogy: I

As you consult this online appendix, keep in mind that the use of periods and capitalization may not be consistent in all sources. The abbreviations and acronyms are provided as a guideline only, not as a definitive reference. Also note that there are many abbreviations that can mean more than one thing; to avoid confusion or misinterpretation, it’s a good idea avoid using these in your citations.

Abbreviations & Acronyms Index:

Genealogy Terms: [A] [B] [C] [D] [E] [F] [G] [H] [I] [J-K-L] [M] [N] [O-P] [Q-R] [S] [T] [U-V-W-X-Y-Z] [Countries] 
[Irish Counties, by Chapman's Codes] [Census & Soundex]
[Miscellaneous Geography Terms] [Computer Terms]

Abbreviations & Acronyms: I

I -- inmate
ib. or ibid. -- ibidem (in the same place)
i.e. -- id est (that is)
IGHR -- Institute of Genealogical and Historical Research (Samford University, Birmingham, Alabama)
IGI -- International Genealogical Index
ign. -- ignorant
IGS -- Institute of Genealogical Studies (Dallas Genealogical Society, Dallas, Texas)
illeg. -- illegitimate
illus. -- illustrated
imp. -- importation
inc. -- incorporated; incomplete
incl. -- included; inclusive
Ind. -- Indians
IND.S.C. -- Indian Survivors' Certificates
Ind. T. or Ind. Ter. -- Indian Territory
Ind. W.C. -- Indian Widow's Certificate
inf. -- infant; infantry; informed
info. -- information
infra -- below, beneath
inh. -- inherited
inhab. -- inhabitant
inq. -- inquiry
ins. -- insert
inst. -- institute; institution; instant (indicates the date referred to was in the same month as a date mentioned previously)
int. -- intentions; interested; interred
inv. or invt. -- inventory
i.p.m. -- inquisitio post mortem (investigation after death)
ISBGFH -- International Society of British Genealogy and Family History
I.T. -- Indian Territory

Abbreviations & Acronyms Index:

Genealogy Terms: [A] [B] [C] [D] [E] [F] [G] [H] [I] [J-K-L] [M] [N] [O-P] [Q-R] [S] [T] [U-V-W-X-Y-Z] [Countries] 
[Irish Counties, by Chapman's Codes] [Census & Soundex]
[Miscellaneous Geography Terms] [Computer Terms]