puny
Word family
Synonym discussion
Sense: adjective/1
While all five words describe a lack of physical strength or size, each carries a different shade. Weak is the most general and can apply to anything from a weak signal to a weak argument. Puny specifically emphasises smallness combined with weakness, often with a slightly scornful tone — a puny arm suggests both thin and useless. Feeble focuses on a lack of energy or force: a feeble attempt is one that gives up quickly. Frail adds a sense of delicacy and vulnerability, as in a frail old lady who breaks a bone easily. Undersized is the most neutral of the group — it simply means smaller than the expected size without suggesting weakness. For example, a puny plant might be yellow and drooping, whereas an undersized plant might just be short but healthy.
Etymology
Puny comes from the Anglo-Norman French word puisné (later-born, younger), which was formed from puis (afterward, from Latin postea) and né (born, from Latin natus). In the 1500s, English adopted it first to mean 'junior' or 'the younger of two people' — for example, a younger son was sometimes called a 'puny' in legal documents. Because younger children are often smaller and weaker than their older siblings, the word gradually shifted to mean 'small and weak' by the late 1500s. The modern sense of 'insignificant' or 'unimpressive' grew out of this physical meaning in the centuries that followed.