DictionaryruntSmall or weak individual
noun

runt

RUNT/rʌnt/

An unusually small or weak individual, especially the smallest in a litter.

The runt nestles beside three noticeably larger puppies.

Four young puppies from one litter rest together, with one clearly smaller puppy nestled beside its three larger littermates.
Etymology

The origin is obscure. Earlier animal uses referred to small cattle and then undersized animals generally, before the word specialized to the smallest member of a litter.

In context

Wildflower Valley Farm4:39
I do have experience with what amounts to having a runt in the litter
Runt of the litter - how to supplement a baby rabbit

More examples

  • They fed the runt separately.
  • Several litters included runts.
  • The runt soon gained strength.

Forms

runt · runts

Similar words

weakling
Emphasizes lack of strength, not necessarily small size.
underling
Means a subordinate person, not a small animal.