Also referred to as a "rec room" in the States!

I wouldn't call it a "rec room" because that's a room in a house.

The answer in English depends on the context. If it's an educational play center in a school or library it would be a play room or play center/centre.

If it's a commercial space with video games and pinball machines, then it's an arcade or game room.

Objectors will say that 'toy library' is too narrow a concept to describe ludotecas in Portugal because a ludoteca is typically a play centre for children staffed by play leaders and organising a huge range of play and leisure activities. They will also say that not all (or even not many) ludotecas actually lend toys to children to take home.

I've just spent an enjoyable half hour reading about various ludotecas in Portugal and toy libraries in the UK, Western Australia, the USA and New Zealand. These are my conclusions: Portuguese ludotecas are more oriented to providing play space, toys and play leadership ON SITE, though several (but not all) also lend toys (Cascais is a good example); toy libraries in the Anglosphere are by no means purely libraries where children can borrow toys - almost all have play rooms and many also have play leaders.

The difference is mainly one of emphasis - the ludoteca is more oriented towards play space, with lending as a minority role; the toy library is perhaps equally oriented towards lending toys and providing play space. I don't think the relative difference justifies ruling out 'toy library' as an adequate translation of 'ludoteca'.

Incidentally, 'toy library' is the established term all over the English speaking world - UK, USA, Canada, the Antipodes - which makes a nice change.

Sug.

Em função da definição de lúdico, creio ser isto aí.

lú.di.co
adj (lat ludu+ico2) Que se refere a jogos e brinquedos ou aos jogos públicos dos antigos. (Michaellis)