How many letters does the top answer for “the internal supporting structure that gives an artifact its shape” have?

The most common answer is skeleton (8 letters).

Crossword clue: the internal supporting structure that gives an artifact its shape

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

skeleton 8 letters wn-def

the internal supporting structure that gives an artifact its shape

underframe 10 letters wn-def

the internal supporting structure that gives an artifact its shape