ふ老fuけるkeruふ化fuけるkeru
1.
To appear older than one's actual age, often due to physical changes or a mature demeanor that suggest an advanced age.
2.
To undergo changes associated with aging, resulting in a noticeable decline in youthfulness or vitality.
3.
To develop an older appearance, typically marked by characteristics that imply an aging process, regardless of chronological age.
Example:
気苦労で彼は急にふけた。