e·nig·ma 
(ĭ-nĭgmə)
(ĭ-nĭgmə)n. pl. e·nig·mas also e·nig·ma·ta (-mə-tə)
1. One that is puzzling, ambiguous, or inexplicable.
2. A perplexing speech or text; a riddle.
[Latin aenigma, from Greek ainigma, from ainissesthai, ainig-, to speak in riddles, from ainos, fable.]
- inasmuch as
- in a/some measure
- in at/on the kill
- inattention
- inattentive
- inattentively
- inattentiveness
- in at the kill
- inaudibility
- inaudible
- inaudibly
- inaugural
- inaugurate
- inauguration
- inaugurator
- inauspicious
- inauspiciously
- inauspiciousness
- inauthentic
- inauthenticity
- in a way
- in a word
- in bad
- in behalf of
- in between