noun
mentsuyu; noodle soup base
A concentrated seasoning liquid for noodle dishes, typically made from dashi, soy sauce, mirin, and sugar. Used diluted as a dipping sauce or soup broth.
See also: 返し (かえし)
ざるそばをめんつゆにつけて食べる。
I eat chilled soba by dipping it in mentsuyu.
うどんの汁は、めんつゆをだしで割って作ります。
The broth for udon is made by diluting mentsuyu with dashi.
返し (kaeshi) is a mixture of soy sauce, mirin, and sugar used as a base for soba tsuyu; mentsuyu is a ready-to-use blend that already includes dashi.
Compound of 麺 (men, 'noodles') and 汁 (tsuyu, 'soup/broth').