A great deal of morphology happens at the ends of words. A suffix is an affix attached after a root or stem to mark grammatical features or to derive new words.

English inflectional suffixes include plural -s and past -ed; derivational suffixes include -ness and -er. Suffixes may stack in languages that allow complex word structures. Stress and spelling rules often interact with suffixation.

Learners benefit from recognizing productive suffixes when guessing meaning and word class. Historical fusion can make suffix boundaries unclear. Worldwide, suffixing is among the most common morphological strategies.

• Affix attached after a root or stem
• Serves inflectional or derivational functions
• Highly productive in many languages
• Supports meaning and category identification