Origin and history of transit

mid-15c., transite, "passageway; c. 1500, "act or fact of passing across or through, the passing of people to and fro," from Latin transitus "a going over, passing over, passage," verbal noun from past participle of transire "cross over, go over, pass over, hasten over, pass away," from trans "across, beyond" (see trans-) + ire "to go" (from PIE root *ei- "to go").

The meaning "a passing of a planet across the sun" (as seen from Earth) is from 1660s. The meaning "public transportation" is attested from 1873.

mid-15c., transiten, "pass, pass through or over," from Latin transitus, past participle of transire "cross over, go over, pass over, hasten over, pass away," from trans "across, beyond" (see trans-) + ire "to go" (from PIE root *ei- "to go"). The astronomical sense of "pass over the disc of a heavenly body" is from 1680s. Related: Transited; transiting.