The Chinese word for four (pinyin: sì), sounds very similar to the word for death (pinyin: sǐ). Similarly, the Sino-Japanese and Sino-Korean words for four, shi (Japanese) and sa (Korean), sound identical to death in each language (see Korean numerals and Japanese numerals). Special care may be taken to avoid occurrences or reminders of the number 4 during festive holidays, or when a family member is sick, especially in Chinese culture. Similarly, 14, 24, etc. are also to be avoided due to the presence of the digit 4 in these numbers. In these countries, these floor numbers are often skipped in buildings, ranging from hotels to offices to apartments, as well as hospitals. Table number 4, 14, 24, etc. are also often left out in wedding dinners or other social gatherings in these countries. In many residential complexes, building block 4, 14, 24 etc. are usually replaced with block 3A, 13A, 23A, etc. In Taiwan, tetraphobia is so common that there are no 4's or x4's for addresses, car number plates and almost everything numerically-related.
The Chinese also show this by having their designations for military aircraft start with the number 5, as in the fighter plane "Shenyang J-5". Similarly the Taiwanese and the South Korean navies do not use the number 4 when assigning Pennant numbers to their ships.
In cities where East Asian and Western cultures blend, such as in Hong Kong and Singapore, it is possible in some buildings that both 13 and 14 are skipped as floor numbers along with all the other 4's.
In Korea, tetraphobia is less extreme, but the floor number 4 is almost always skipped in hospitals and similar public buildings. In other buildings, the fourth floor is sometimes labeled "F" (Four) instead of "4" in elevators. Apartment numbers containing multiple occurrences of the number 4 (such as 404) are likely to be avoided to an extent that the value of the property is adversely affected.