if: a "what-if" (hypothetical alternative history, or an alternative retelling of fictional events)

"what-if" alternative history (real-life) / events (fictional)

Alternative letter-case form of if

a road or path, (often) a highway / a course, an itinerary of stops, as for a bus / a path or course for information / a path or course for goods in a transaction / (video games, storytelling) storyline

(mathematics) a root (as in a square root) / (linguistics) an etymological root / (music) root note in a chord

back channel

Obsolete spelling of テネシー (Teneshī, “Tennessee (a state of the United States)”)