rare0. [Etymology unknown.] = INGATE sb.2: see quots.

1

1858.  Simmonds, Dict. Trade, Ingate, an aperture in a mould for pouring in metal; technically called the tedge.

2

1877.  Knight, Dict. Mech., Tedge, the ingate or aperture in a mold through which the molten metal is poured.

3