(a) Chapter.— The following words and phrases when used in this chapter shall have the meanings given to them in this subsection unless the context clearly indicates otherwise:

1. "Joint coverage member." A city employee who becomes a member of the retirement system subsequent to the last date permitted by the city for statement or preference concerning Social Security coverage or who, having become a member on or before that date, filed a written statement with a city's retirement board that the member elects Social Security coverage under an agreement with the Secretary of Health and Human Services entered into by the Commonwealth.
2. "Single coverage member." A city employee who becomes a member of the retirement system on or before the last date permitted by the city for statement of preference concerning Social Security coverage and who either filed a written statement with the retirement board that the member does not elect Social Security coverage under any agreement with the Secretary of Health and Human Services entered into by the Commonwealth or did not file any written statement with the retirement board.

(b) Subchapter.— The following words and phrases when used in this subchapter shall have the meanings given to them in this subsection unless the context clearly indicates otherwise:

1. "Salary." The fixed amount of compensation paid at regular, periodic intervals by the city to the member and from which pension contributions have been deducted.