Answer:
Let's go through each sentence and determine the synonym for the italicized compound word:
1. You've got a new wristwatch which is similar to my two-year-old timepiece.
- Synonym for "wristwatch": timepiece
2. The clock hands and numerals are luminous or light-emitting for they glow even in the darkest place.
- Synonym for "luminous": light-emitting
3. Self-winding watches became popular in the 1920's so did automatic clocks.**
- Synonym for "self-winding": automatic
4. The schedule of flights to the south is as tight as the timetable of sea trips.
- Synonym for "timetable": schedule
5. Celebrating a fiesta is a time-honored Filipino tradition that dates back as a long established Spanish culture centuries ago.
- Synonym for "time-honored": long established
### Summary of Synonyms
1. Wristwatch – **Timepiece**
2. Luminous – **Light-emitting**
3. Self-winding – **Automatic**
4. Timetable – **Schedule**
5. Time-honored – **Long established**
