Glossary · Word parts and vocabulary
What is a derivational suffix?
Definition
A derivational suffix makes a new word from a base, often changing its part of speech, as -ness turns kind into kindness and -ful turns hope into hopeful.
Where inflectional endings keep a word the same word, derivational suffixes build new ones. Teach becomes teacher (a person), happy becomes happiness (a noun), quick becomes quickly (an adverb).
There are dozens of them, and the common ones are worth teaching by meaning: -ful (full of), -less (without), -ness (state of), -ly (in a way), -er and -or (one who), -able (can be), -tion (act of).
Derivational suffixes are where reading, spelling and vocabulary meet. A student who knows -able can read washable, spell it, and work out that it means can be washed, all from one lesson. That's a lot of return for a three-letter part.
In a lesson
Write teach, teacher, teachable. The student names the part of speech of each and explains what the suffix added. Then they try one of their own with paint.
Examples
Each word with its spelling units, one per sound.
- washablew·a·sh·a·b·le
- kindnessk·i·n·d·n·e·ss
- actiona·c·tion
Words come from our lexicon, checked against a pronouncing dictionary. Words a student sees in our assessments are left out.
Why does this matter for the record?
Track the derivational suffixes taught as a list with meanings. Check meaning with a new word, not a practiced one.
Rate each skill as you teach it
Needs support, Developing, Secure. The rating schedules the review and builds the report.