1. (noun) an addition to the length of something

• extension

1. (noun) the quality of being elongated

• longness

2. (noun) an addition to the length of something

• add-on
• addition
• improver

3. (noun) the act of lengthening something

• change of shape

1. (noun) the quality of being elongated

• elongate
• stretch

2. (noun) an addition to the length of something

• elongate
• stretch

3. (noun) the act of lengthening something

• elongate
• stretch