cabellar

An obsolete verb meaning to grow hair (echar cabello) or to wear a wig/false hair — also historically used for corn cobs growing their silky 'hair.' Entirely displaced in modern Spanish by descriptive phrases like crecer el pelo or salir el pelo.

• Los textos antiguos decían que el niño ya empezaba a cabellar. — Old texts said the boy was already starting to grow hair.
• Las mazorcas cabellaban en pleno verano. — The corn cobs were growing their silk in high summer.
• Una dama de la época podía cabellar con una peluca. — A lady of the period might wear false hair with a wig.

This verb is essentially dead in modern Spanish — a learner should use crecerle el pelo a alguien ('for hair to grow on someone') for the everyday sense instead of trying to use cabellar.