时 (shí) — (noun) time, period, season; (classifier) hour (used after numbers; also seen in 小时)

时 (shí) is a single-character time word used mostly inside compounds like 小时 (hour) or 那时 (at that time). As a standalone it leans literary/classical; in modern speech reach for 时间 or 时候 instead.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 時; 时 is its simplified writing.

The traditional form 時 pairs 日 (sun/day) with 之 as the part that gives the sound; the simplified 时 is not the form described.