nounainmfhocal1cul-de-saccaochbhealachmasc1cmu2unsuccessful course of actionhe did a lot of research on it but it ended up being a blind alleyrinne sé a lán taighde air ach saothar in aisce a bhí ann, rinne sé cuid mhór taighde air ach ní raibh dada ar a shon aige