This is the 8857th most frequent Catalan word.
estira
"Estira" in English means "pulls" or "stretches."
Here, 'estira' is used as the conjugated form of the verb 'estirar' meaning 'to pull' in the present tense for the third-person singular.
Ell estira la corda amb força.
He pulls the rope firmly.
In this case, 's'estira' indicates a reflexive use of 'estirar', where the fabric is stretching itself, showing flexibility.
La tela es tan elàstica que s'estira fàcilment.
The fabric is so elastic that it stretches easily.
Here, 'd'estira-se' refers to a reflexive action meaning 'to stretch' oneself, such as warming up one’s muscles.