The verb qel ("nod") refers only to the motion of the head, not what such a motion may or may not indicate. To express that the nodding means something, such as agreement, you could say something like Qochbe' vaj qel nachDaj ("he/she agrees so his/her head nods").

It is also possible to make use of ghaS ("indicate, signal"), for example, Qochbe' 'e' ghaSmeH qel nachDaj ("His/her head nods in order to indicate that he/she agrees") or Qochbe' 'e' ghaSmeH qel ghaH ("He/she nods in order to indicate that he/she agrees" or "He/she nods in agreement").

In some cultures, a nod may indicate something other than agreement, so one might say, for example, yaj 'e' ghaSmeH qel ghaH ("He/she nods to signal that he/she understands").

(qepHom 2020)

To say "X means Y" (where X is a word and Y is its meaning or definition or gloss), use ghaS, sometimes along with mu' for clarity: Y ghaS X (mu').

A colloquial (or perhaps slang) way of expressing the definition of a word within the same language – not when translating – is to use 'ang instead of ghaS: Y 'ang X (mu').

X could, of course, be a phrase. If so, it can be followed by either mu' or mu'mey, more frequently the former.

(qep'a' 2022)