analysis, count, counting, empiricism, enquiry, enumeration, examination, inquiry, numeration, reckoning, research, scrutiny, search, tabulation, tally, tap, testing, wiretap.
abbreviation, abdication, aberration, ablation, abnegation, abomination, abrogation, acceleration, acclamation, acclimation, accommodation, accreditation, accumulation, accusation, accusation, acidification, activation, adaptation, adjudication, administration.
Your query has returned 717 words, which include anagrams of investigation as well as other shorter words that can be made using the letters included in investigation.
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