The rules for building up words from bits and pieces

Understanding morphology shapes our knowledge of language.

In an earlier post, we discussed morphemes. Here, we discuss the study of morphemes, called Morphology. Linguists study morphology by studying how people learn and use morphemes, and how morphemes interact with each other when they are put together. One common purpose of morphemes is to change a word’s part of speech.

For example, adding the morpheme -able to a verb makes the new word an adjective.

  • Run + “able” = runnable
  • Lock + “able” = lockable
  • Love+ “able” = lovable

Similarly, adding un- to a verb reverses the action the plain verb does, but adding un- to an adjective negates it.

  • “Un” + lock = unlock
  • “Un” + cool = uncool
  • “Un” + interesting = uninteresting

Sometimes, this creates ambiguities like the word unlockable.

  • “Un” + lock + “able” = unlockable
  • “Un” + do + “able” = undoable
  • “Un” + zip + “able” = unzippable

In the case of unlockable, does this word mean the lock can be unlocked?

A functioning open lock and key

Or does it mean the lock cannot be locked?

A padlock that has been cut apart.

Actually, it can mean either interpretation! There are lots of ambiguous words like unlockable. Unzippable and undeletable are two more examples. The only way to be certain what meaning is meant, we need context! One meaning might seem more obvious than the other. Some linguists study why that is, or if either meaning seemed equally possible, they study that too!

Languages vary in how they use morphology to share meaning. English relies a lot on syntax to hold information, but other languages use morphemes way more, such that they can carry the equivalent of an entire English sentence in what we would consider to be one word. Swahili is one of those languages.

“Tunawapenda” carries all the information in the English sentence “We love them.” Similarly, “Ninawapenda” means “I love them”

Tu (We) na (present) wa (them) penda (love), Ni (I) na (present) wa (them) penda (love).
A gloss of the two Swahili words.

Instead of being carried in individual words, the information is carried in morphemesMorphologists study how information is shared in these different ways.

When babies learn languages, they don’t know whether they’ll be learning a language like English or Swahili. They have to figure this out along the way! Infant language researchers often incorporate morphology to investigate how and when babies learn to understand and use morphemes.

Aahnix poses for a picture on a chair, facing the sunset.

Aahnix Bathurst


Aahnix is a Project Coordinator in the Bergelson lab at Duke University

Elika Bergelson

Principal Investigator