Glume and Lemma

Glume noun - Small dry membranous bract found in inflorescences of Gramineae and Cyperaceae.

Lemma and glume are semantically related. In some cases you can replace term "Lemma" with "Glume", this nouns are similar.

Lemma noun - The lower and stouter of the two glumes immediately enclosing the floret in most Gramineae.

Glume and lemma are semantically related. Sometimes you can use "Glume" instead a noun "Lemma".