You searched for: “staid
staid (adjective); staider, staidest
Dignified and serious in habit or behavior, and even boring: Charles was considered to be a solemn and staid member of the company's administrative staff.

The politician had a staid manner when he was asked personal questions about his family.

staid, stayed
staid (STAYD) (adjective)
Characterized by self restraint; serious, boring, or old fashioned: "His staid manner was in contrast to the bright red sports jacket he was wearing."
stayed (STAYD) (verb)
1. To have paused or stopped a forward movement: "The deer stayed perfectly quiet until the hunter got close to it."
2. To have lived or resided in some location: "We stayed in a lovely Bed and Breakfast near the river for our vacation."
3. To stop or to delay a proceeding, often in a legal context.: "The judge stayed the court order until she heard the new evidence."

Because of his important responsibilities, the officer always stayed staid throughout his career.